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CB8 Manual

INTRODUCTION

As a leading manufacturer of smart function modules, NAI offers over 100 different modules that cover a wide range of I/O, measurements and simulation, communications, Ethernet switch, and SBC functions. Our CAN Bus smart function modules provide independent, isolated, channels of CAN serial data bus links, conforming to the ISO 11898 International Standard.

CAN (Controller Area Network) is a multi-master, broadcast, serial bus standard for connecting Electronic Control Units (ECUs) in the automotive, aerospace, marine, industrial automation and medical equipment industries. ISO 11898 defines the CAN serial bus system and specifies its architecture and operating parameters. Module CB8 conforms to CAN Specification 2.0, parts A and B, provides Flexible Data (FD) communication, and conforms to ARINC 825-4, which supports both CAN 2.0 and CAN FD. The CAN protocol was developed by Robert Bosch GmbH and is recognized and protected by patents and licensed by Bosch.

This user manual is designed to help you get the most out of our CAN Bus smart function modules.

For a brief description of the function and features of the CB8, click here for the CB8 Data Sheet

CB8 Overview

NAI’s CB8 modules offers a range of features designed to suit a variety of system requirements, including:

Eight Independent Fully Isolated CAN Bus Communication Channels: The CB8 provides eight independent CAN bus channels, each with full isolation to help protect against electrical noise, ground potential differences, and fault propagation. This architecture supports reliable operation across multiple networks at the same time while improving overall system robustness.

Supports ISO-11898 CAN 2.0A and CAN 2.0B Protocols: This module supports both CAN 2.0A and CAN 2.0B in accordance with ISO-11898, enabling compatibility with both 11-bit and 29-bit identifier message formats. This allows the device to interface with a broad range of standard CAN-based systems and equipment.

CAN FD Support for Higher Bandwidth Communications: The CB8 supports CAN FD, which increases communication bandwidth by allowing higher data rates during the data phase and larger payload sizes than Classical CAN. This makes the module well suited for applications that require more efficient transfer of larger amounts of data.

ARINC 825-4 Avionics CAN Protocol Support: The CB8 supports ARINC 825-4, a CAN-based avionics protocol standard used in aerospace systems. This capability allows the module to be integrated into aircraft and other avionics applications requiring standardized CAN communications.

Programmable Bit Rate Configuration per Channel: Each CAN channel can be independently configured for its required communication speed, allowing the module to support multiple networks with different baud rate requirements. This flexibility simplifies integration in mixed-system environments.

  • Up to 1 Mbps per channel (Classical CAN) For standard Classical CAN operation, each channel can run at speeds up to 1 megabit per second. This covers the typical maximum rate used in many industrial, vehicle, and control applications.

  • Up to 4 Mbps data phase (CAN FD) In CAN FD mode, the module can increase the speed of the data portion of the frame to as much as 4 megabits per second. This allows faster transfer of payload data while maintaining CAN-compatible arbitration behavior.

Supports Standard, Extended, and Remote CAN Frames: This module supports Standard, Extended, and Remote CAN frames, allowing compatibility with a wide variety of message types used across CAN networks. This ensures the device can operate effectively in systems using different addressing and request formats.

  • Extended Data Payload Support (CAN FD): With CAN FD, the CB8 supports larger data payloads than Classical CAN, allowing more information to be transmitted in a single frame. This reduces message overhead and improves bus efficiency in data-intensive applications.

8 Maskable Identifier Filters per Channel: Each channel includes eight programmable identifier filters that can be masked to selectively accept or reject messages. This helps reduce processor overhead by allowing only relevant traffic to pass through to the application.

Filtering on Message ID and First Two Data Bytes: In addition to filtering by CAN identifier, the module can also filter based on the first two bytes of the data field. This provides more granular message selection and improves control over received traffic.

Independent Transmit and Receive FIFOs per Channel: Each channel includes dedicated transmit and receive FIFO buffers to manage outgoing and incoming messages separately. This improves message handling efficiency and helps prevent data loss during periods of heavy bus activity.

Programmable Line Termination: The CB8 supports programmable line termination, allowing CAN bus termination settings to be configured as needed for the application. This simplifies system integration and helps maintain proper signal integrity on the network.

Continuous BIT: All channels support Continuous Built-In Test (BIT), allowing the module to monitor operational health during runtime. This supports early fault detection and improves reliability in mission-critical systems.

DO-254 DAL A Certifiable IP Core (Pending, Contact Factory): The module is designed to support a DO-254 DAL A certifiable IP core, intended for use in the highest-assurance airborne hardware applications. Because this capability is listed as pending, factory coordination is required for current certification status and availability.

PRINCIPLE OF OPERATION

CB8 provides the CAN data link layer protocol as standardized in ISO 11898-1 (2003). It can also provide Flexible Data (FD) communication, which is an extension of that ISO standard. The standard describes the data link layer (composed of the logical link control (LLC) sublayer and the media access control (MAC) sublayer) and some aspects of the physical layer of the OSI reference model. All the other protocol layers are the network designer’s choice.

Each CAN node can send and receive messages, but not simultaneously. A message consists primarily of an ID (identifier), which represents the priority of the message, and up to 8 (64 for CAN FD) data bytes. The devices that are connected by a CAN network are typically sensors,actuators, and other control devices. These devices are not connected directly to the bus, but through a host processor and a CAN controller.

If the bus is idle, which is represented by recessive level (Logical 1), any node may begin to transmit. If two or more nodes begin sending messages at the same time, the message with the more dominant ID (which has more dominant bits, i.e., zeroes) will overwrite other nodes' less dominant IDs, so that eventually (after this arbitration on the ID) only the dominant message remains and is received by all nodes. This mechanism is referred to as priority-based bus arbitration. Messages with numerically smaller values of IDs have higher priority and are transmitted first.

When utilized, CAN FD communication provides nodes with the capability to send more payload data at faster speeds over a conventional CAN A/B network. The electrical condition/configuration of the CAN Bus (total number of units connected, length of the CAN Bus wires, other electromagnetic factors) determine the fastest data transfer rate possible on that CAN Bus. It also provides better error detection in received CAN messages.

Each node (the CAN module on an appropriate board/system platform is a node) provides:

Host Module Processing

The host (on-module) processor decides what received messages mean and which messages it wants to transmit itself. Sensors, actuators, and control devices can be connected to the host processor.

For the CB8, 8 channels of CAN FD are available. Each channel can be viewed as a separate CAN Bus.

The BareMetal application has a control loop that services each of these inboard channels sequentially in a single thread. Depending on the commands sent to the BareMetal application, a different amount of functionality may be performed for each channel when it is their turn to run. Regarding CAN FD functionality, for versions of the BareMetal where the Enhanced Last Error Code compatibility bit is not set, the BareMetal application will cycle through all channels checking for incoming commands, in addition to performing any Rx and Tx actions for each channel before it relinquishes processing control. For BareMetal versions that have the Enhanced Last Error Code compatibility bit set, the BareMetal application will only process one (target) channel on any given pass before relinquishing processing control. This 'target channel to process' moves to the next channel so during the next CAN FD run period, a different target channel is processed. The reason for this “round-robin” approach to processing the CAN channels is that CAN FD processing was determined to be taking longer than was expected due to the processing of both channels before relinquishing control. By processing only an individually selected channel during a run period, the other modules are now processed in a timelier manner, reducing the overall processing loop time.

Another factor impacting the amount of time spent processing CAN FD is the frequency of messages that need to be sent or received during the CAN FD processing cycle for the channel(s) being processed. The BareMetal application for CAN FD measures MAX_WORK_TIME in milliseconds (ms). The 'non-round-robin' versions of the BareMetal code contain a default value of 1000ms (approximately 1 second). Users of these versions of the BareMetal can set this MAX_WORK_TIME to any value from 0 to 4,294,967,295 (max unsigned integer 32-bit value). If set to 0, however, the 'non-round-robin' versions of the BareMetal will automatically assign the MAX_WORK_TIME to the default value (1000ms). The least amount of time the user can set the MAX_WORK_TIME to be is 1ms.

This logic was changed with the 'round-robin version' of the BareMetal. Now, the default MAX_WORK_TIME in milliseconds is 0. This means that when transmitting or receiving CAN FD messages, the most that will be processed is 1 message before CAN FD relinquishes processing control. During each CAN FD processing cycle, the control register is checked for any requested commands to be performed (bit by bit). If any bits return a value of 1, that command’s desired action is performed. When the action is finished, the corresponding control bit is set back to 0 to indicate that the action was completed by the BareMetal functionality. After all the applicable control bits are processed, a check is made to see if transmit for the channel being processed is enabled. If transmit is enabled, the BareMetal will try to transmit data found in the transmit FIFO. After transmitting each full message, a timer is checked to see how much time has been spent in the transmit function. If this time exceeds the MAX_WORK_TIME, the transmit function will exit even if there is still additional data in the transmit FIFO to send. This time limit helps to prevent delaying the other function modules from being serviced.

After the transmit function is finished, the receive function is called, which probes the CAN FD IP to determine if any messages are available for retrieval. If there are available messages for retrieval, a logic like what is used for the transmit function regarding the MAX_WORK_TIME allowed is performed. Full CAN FD messages are read from the CAN FD IP and copied to the receive FIFO. The retrieval of messages will continue if there are messages to be received or until the MAX_WORK_TIME has been exceeded. In either case the receive function will exit and the CAN FD will relinquish control back to the BareMetal main routine allowing the next function module in the queue to be processed.

CAN Controller: Hardware with a Synchronous Clock

Receiving: the CAN controller stores received bits serially from the bus until an entire message is available and put in the FIFO, which can then be fetched by the host processor (usually after the CAN controller has triggered an interrupt or is polling for messages).

Sending: the host processor stores the transmit messages onto a CAN controller, which transmits the bits serially onto the bus.

Transceiver

Receiving: it adapts signal levels from the bus to levels that the CAN controller expects and has protective circuitry that protects the CAN controller.

Transmitting: it converts the transmit-bit signal received from the CAN controller into a signal that is sent onto the bus. With CAN A/B, bit rates up to 1 Mbit/s are possible at network lengths below 40 m. Decreasing the bit rate allows longer network distances (e.g., 500 m at 125 kbit/s). With CAN FD, bit rates up to 4 Mbit/s are possible at network lengths below 40 m (Note: this is for data payload only; the arbitration bit rate is still limited to 1 Mbit/s for compatibility). Decreasing the bit rate allows longer network distances (e.g., 500 m at 125 kbit/s). CAN FD extends the speed of the data section by a factor of up to 8 (64 bytes) of the arbitration bit rate over what classic CAN provides (8 bytes). The CAN FD frame/message ID uses an Extended ID (29-bit format) version of the classic CAN Standard ID (11-bit) format. CAN FD can also handle Standard ID formatted messages, as well.

As applications may require many nodes (SG), which are not predetermined, both conventional CAN A/B bus and CAN FD bus require proper termination (120-ohm resistor at each end of the bus) to operate properly. A new feature to NAI’s CAN FD module is the ability to assign termination to desired channels in code rather than requiring a physical resistor to be attached.

CB8 img01

Continuous Background Built-in Test (BIT)/Diagnostic Capability

BIT is performed in the background continuously within the FPGA. Each channel is checked periodically at 80MHz for correct operation. Any failure triggers an interrupt if enabled, with the results available in the status registers. The testing is transparent to the user and has no effect on the operation of the CB8.

REGISTER DESCRIPTIONS

The register descriptions provide the register name, Register Offset, Type, Data Range, Read or Write information, Default Value, a description of the function and, in most cases, a data table.

Receive Registers

The registers listed are associated with data that is received on the CAN Bus channels

Receive FIFO Buffer Data

Function:

Stores received messages.

Type:

unsigned binary word (32-bit)

Data Range:

0x0000 0000 to 0xFFFF FFFF

Read/Write:

W-H, R-A
NOTE: 'H' is 'Host; 'A' is 'ARM'

Operational Settings:

N/A

Default:

0

CAN Frame as it is to be read off the FIFO - The FIFO contains 32-bit values where the top 8 bits are reserved for flags. The payload is “packed” where up to 3 x 8-bit values are stuffed into 1 x 32-bit read from the FIFO (upper 8 bits are always reserved for flags)

Description

Bits Read

Meaningful Bits

NOTES

Msg ID - Lower 16

32

Lower 16 (0x0000FFFF)

Lower and Upper make up 29 Bit Identifier

Msg ID - Upper 16

32

Upper 16 (0x0000FFFF)

Timestamp - Lower 16

32

Lower 16 (0x0000FFFF)

Lower and Upper Timestamp

Timestamp - Upper 16

32

Upper 16 (0x0000FFFF)

Msg/Payload Length

32

1 Byte (0x000000FF)

Length of Msg (payload count)

Payload Data is “Packed” - lower 24 bits make up 3 x 8 bits of data. Top 8 bits are reserved for flags.

Data[0], Data[1], Data[2]

32

Data[0]

X

1st Byte (0x000000FF)

1st Byte is Data[0]

Data[1]

X

2nd Byte (0x0000FF00)

2nd Byte is Data[1]

Data[2]

X

3rd Byte (0x00FF0000)

3rd Byte is Data[2]

If msg length indicates more data to read…another 32 bits would be read from the FIFO

Data[3], Data[4], Data[5]

32

Data[3]

X

1st Byte (0x000000FF)

1st Byte is Data[3]

Data[4]

X

2nd Byte (0x0000FF00)

2nd Byte is Data[4]

Data[5]

X

3rd Byte (0x00FF0000)

3rd Byte is Data[5]

This continues until Data[MsgLen -1]

Receive FIFO Word Count

Function:

Contains the number of 32-bit words in the Receive FIFO buffer.

Type:

unsigned integer word

Data Range:

0 to 1048576 (0 to 0x0010 0000)

Read/Write:

R

Operational Settings:

N/A

Default:

0

Receive FIFO Frame Count

Function:

Contains the number of frames in the Receive FIFO buffer.

Type:

unsigned integer word

Data Range:

0 to 409 (0 to 0x0000 0199) (Minimum CAN frame will be 5 entries on the FIFO)

Read/Write:

R

Operational Settings:

Each minimum CAN frame is 5; 32-bit words that get placed on the FIFO. Maximum frame count is thus 2048 (0x0000 0800) / 5 = 409 (0x0000 0199).

Default:

0

Transmit Registers

The registers listed are associated with data that is transmitted on the CAN Bus channels.

Transmit FIFO Buffer Data

Function:

Transmits messages in FIFO

Type:

unsigned binary word (32-bit)

Data Range:

0x0000 0000 to 0xFFFF FFFF

Read/Write:

W-H, R-A
NOTE: 'H' is 'Host; 'A' is 'ARM'

Operational Settings:

N/A

Default:

0

CAN Frame as it is to be read off the FIFO - The FIFO contains 32-bit values where the top 8 bits are reserved for flags. The payload is “packed” where up to 3 x 8-bit values are stuffed into 1 x 32-bit read from the FIFO (upper 8 bits are always reserved for flags)

Description

Bits Read

Meaningful Bits

NOTES

Protocol

32

0xFF00000F

Valid Protocol values are 0 and 1. Flag for Start of message is 0x80000000

Msg ID - Lower 16

32

Lower 16 (0x0000FFFF)

Lower and Upper make up 29 Bit Identifier

Msg ID - Upper 16

32

Upper 16 (0x0000FFFF)

Extended ID

32

0x0000000F

Mode A = 0
Extended = 1

Msg/Payload Length

32

1 Byte (0x000000FF)

Length of Msg (payload count). If zero payload, the End of Message Flag (0x10000000) will be set

Payload Data is “Packed” - lower 24 bits make up 3 x 8 bits of data. Top 8 bits are reserved for flags.

End of Message Flag (0x10000000) will be set on the last payload data value only.

Data[0], Data[1], Data[2]

32

Data[0]

X

1st Byte (0x000000FF)

1st Byte is Data[0]

Data[1]

X

2nd Byte (0x0000FF00)

2nd Byte is Data[1]

Data[2]

X

3rd Byte (0x00FF0000)

3rd Byte is Data[2]

If msg length indicates more data to read…another 32 bits would be read from the FIFO

Data[3], Data[4], Data[5]

32

Data[3]

X

1st Byte (0x000000FF)

1st Byte is Data[3]

Data[4]

X

2nd Byte (0x0000FF00)

2nd Byte is Data[4]

Data[5]

X

3rd Byte (0x00FF0000)

3rd Byte is Data[5]

This continues until Data[MsgLen -1]

Transmit FIFO Word Count

Function:

Contains the number of 32-bit words in the Transmit FIFO register.

Type:

unsigned integer word

Data Range:

0 to 1048576 (0 to 0x0010 0000)

Read/Write:

R

Operational Settings:

N/A

Default:

0

Transmit FIFO Frame Count

Function:

Contains the number of frames in the Transmit FIFO register.

Type:

unsigned integer word

Data Range:

0 to 409 (0 to 0x0000 0199) (Minimum CAN frame will be 5 entries on the FIFO)

Read/Write:

R

Operational Settings:

Each minimum CAN frame is 5; 32-bit words that get placed on the FIFO. Maximum frame count is thus 2048 (0x0000 0800) / 5 = 409 (0x0000 0199).

Default:

0

Command Registers

The registers listed are associated with functionality which enables Tx and Rx FIFO to be dedicated to sending and receiving CAN FD messages.

BareMetal Capabilities Register

Function:

Determines if the revision of BM can use Command FIFO, response registers and can set the device sample point.

Type:

unsigned integer word

Data Range:

0 to 0x5

Read/Write:

R/W

Operational Settings:

See table below

Default:

0

D31

D30

D29

D28

D27

D26

D25

D24

D23

D22

D21

D20

D19

D18

D17

D16

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

D15

D14

D13

D12

D11

D10

D9

D8

D7

D6

D5

D4

D3

D2

D1

D0

0

0

0

0

0

0

0

0

0

0

0

0

0

D

D

D

Bit

Description

D0

Cmd FIFO in Use: if set to 1, Cmd FIFO is available and can be used to send parameters to the BareMetal.

D1

Sample Point: If set to 1, the BareMetal is capable of setting the sample point to the desired value.

D2

Response Registers: If set to 1, the BareMetal is using these registers to return data instead of the Rx FIFO.

D4:D31

<RESERVED FOR FUTURE>

Command FIFO Buffer Data

Function:

Transmits BareMetal parameters in FIFO

Type:

unsigned binary word (32-bit)

Data Range:

0 to 0xFFFF FFFF

Read/Write:

W-H, R-A
NOTE: 'H' is 'Host; 'A' is 'ARM'

Operational Settings:

N/A

Default:

0

Command FIFO Word Count

Function:

Contains the number of words in the Command FIFO register.

Type:

unsigned integer word

Data Range:

0 to 32 (0 to 0x0000 0020)

Read/Write:

R

Operational Settings:

N/A

Default:

0

Control Registers

The register specified in this section provides the ability to control the operation for each CAN Bus channel.

Control

The control register has been implemented to act solely as a “request for action” register. Bits can be set to a 1 to request various actions or capabilities. When the action or capability is acted upon by the CAN firmware, these request bits will be set back to 0.

Control

Function:

Provides flags for controlling transmit and receive activity.

Type:

binary word (32-bit)

Data Range:

0x0000 0000 to 0x87FF BFF3

Read/Write:

R/W

Operational Settings:

See descriptions that follow.

Default:

0 (disabled)

D31

D30

D29

D28

D27

D26

D25

D24

D23

D22

D21

D20

D19

D18

D17

D16

D

0

0

0

0

D

D

D

D

D

D

D

D

D

D

D

D15

D14

D13

D12

D11

D10

D9

D8

D7

D6

D5

D4

D3

D2

D1

D0

D

0

D

D

D

D

D

D

D

D

D

D

0

0

D

D

Bit

Description

D0

Request Enable Tx: Enables any messages found in the Tx FIFO to be placed on the bus from the current channel.

D1

Request Disable Tx: Stops any messages currently in the Tx FIFO from being put on the bus from the current channel.

D2

<RESERVED FOR FUTURE>

D3

<RESERVED FOR FUTURE>

D4:

Request Set Level Dominant: This is for Debug purposes only and forces channel bus signal to a constant dominant value.

D5

Request Set Level Recessive: This is for Debug purposes only and forces channel bus signal to a constant recessive value.

D6

Request Enable Termination: Internal termination will be enabled for the current channel.

D7

Request Disable Termination: Internal termination will be disabled for the current channel.

D8

Request Base Rate Change: Desired base rate enumerated type value needs to be assigned to the lower 16 bits of the datarate-baserate register. Valid values include 0 (1Mb), 1 (500K), 3 (250K), 7 (125K) and 9 (83.33K)

D9

Request Data Rate Change: Desired data rate enumerated type value needs to be assigned to the upper 16 bits of the datarate-baserate register. Valid values include 6 (4Mb), 7 (3Mb), 8 (2Mb) and 9 (1Mb).

NOTE: Data rate of 3 Mb is not recommended as it has been found to be unreliable.

D10

Request reset of Tx FIFO: Clears the entire Tx FIFO

D11

Request reset of Rx FIFO: Clears the entire Rx FIFO

D12

Request reset of Drop Count: Resets the counter that keeps track of how many messages were dropped due to FIFO already being full.

D13

Request reset of Command FIFO: Clears the entire Command FIFO.

D14:

<RESERVED FOR FUTURE>

D15

Request Reset Channel. Expected for next release: Reset Channel will reset both the Tx, Rx and Cmd FIFOs, disable Tx enable, Clear any Last Error Code, zero out Tx/Rx error counter and drop count registers and reset entire set of response registers. Reset Channel also retains the configured baud rate so the baud rates that were configured prior to the reset will be reassigned after the reset completes back to the same baud rates.

D16:

Request Config Sequencer: Allows caller to configure a given sequencer (schedule). Configuration data is expected to be placed on the Tx FIFO in the following order:

(1) Requested Config Sequencer Cmd ID so we know the data following this is the data needed to configure a new sequencer/schedule.
(2) Sequencer ID (schedule index): 1 based value of schedule to configure.
(3) Protocol: 0 (CAN A/B) or 1 (CAN FD)
(4) Rate: The number of 125us between two transmissions
(5) Skew: The number of 125us after the rate event to transmit the message. (Example: If the rate is 80, then the message is transmitted every 10ms. If two messages have the same rate then it may be wise to stagger the messages a little to avoid collision by setting the skew for the 1 message to 0 and the skew for the 2 message to 2 where 2 * 125us = 250us.
(6) MsgID (low): place lowest 16 bits of MsgID onto FIFO.
(7) MsgID (high): place highest 13 bits of MsgID onto FIFO (zeros if CAN A/B).
(8) Extended ID: 0 (Not Extended 11bit identifier), 1 (Extended 29bit identifier)
(9) Msg (payload) Length: value between 0 and 64 if CAN FD or 0 and 8 if CAN A/B
(10) Msg payload starts..should have Msg Length number of values in the FIFO waiting to be read into a buffer.

D17

Request Start Sequencer/Scheduler: This will start all configured sequencers/schedules

D18

Request Stop Sequencer/Scheduler: This will stop all configured sequencers/schedules

D19

Set Sample Point: Provides flexibility to assign various sample point values (75% or 80%) to the CAN FD core since it is important that all CAN FD devices use the same sample point to detect bit rate switching (BRS).

D20

Request Enable Filters: Enables all filters configured for the current channel.

D21

Request Disable Filters: Disables all filters configured for the current channel.

D22

Request Set Filter: Allows caller to configure a filter (A total of 8 filters can be configured indexed from 0 - 7). Filter configuration data is expected to be placed on the Cmd FIFO in the following order:

(1) Set Filter Cmd ID: so we know the data following this is the data needed to configure a new filter.
(2) Filter Index: A value between 0 and 7 (filter slot to configure).
(3) CAN ID (low): low 16 bits of CAN ID.
(4) CAN ID (high): the highest 16 bits of CAN ID (pushed to the lower 16 bits of this FIFO value).
(5) Extended ID: 1 to only allow extended ID messages, 0 normal CAN A/B messages
(6) First Byte of Payload to filter on (8 bits)
(7) 2 Byte of Payload to filter on (8 bits)

D23

Request Get Filter: Retrieves desired filter data. The following is expected to be on the Cmd FIFO when this control bit value is detected being set:

(1) Get Filter Cmd ID: so we know the data following this is the data needed to get desired filter information.
(2) Filter Index: A value between 0 and 7 of which to fetch filter configuration data.

NOTE: The response data will be made available in the set of response registers.

D24

Request Set Filter Mask: The following data is expected to be on the Cmd FIFO in order to configure the desired Filter Mask. The Filter Mask is used on incoming messages that are received and on the corresponding Filter configuration data that was set where Filter Index = Mask Index. After applying the mask to both, the corresponding bits are compared and if both sides match, the data is received else it is rejected.

(1) Set Filter Mask Cmd ID: so we know the data following this is the data needed to configure a new filter mask.
(2) Mask Index: A value between 0 and 7 (mask slot to configure). NOTE: Mask index is meant to align with desired Filter Index from Set Filter.
(3) CAN ID (low): low 16 bits of CAN ID.
(4) CAN ID (high): the highest 16 bits of CAN ID (pushed to the lower 16 bits of this FIFO value).
(5) Extended ID: 1 to only allow extended ID messages, 0 normal CAN A/B messages
(6) First Byte of Payload to filter on (8 bits)
(7) 2 Byte of Payload to filter on (8 bits)

D25

Request Get Filter Mask: Retrieves desired filter mask configuration data. The following is expected to be on the Cmd FIFO when this control bit value is detected being set:

(1) Get Filter Mask Cmd ID: so we know the data following this is the data needed to get desired filter mask information.
(2) Mask Index: A value between 0 and 7 of which to fetch mask configuration data.

NOTE: The response data will be made available in the set of response registers for the given channel.

D26

Request Remove Filter: Removes desired filter from the filter configuration. The following is expected to be on the FIFO when this control bit is detected being set:

(1) Remove Filter Cmd ID: so we know the data following this is the data needed to remove desired filter information.
(2) Filter Index: A value between 0 and 7 (filter slot to remove filter configuration)

D27

<RESERVED FOR FUTURE>

D28

<RESERVED FOR FUTURE>

D29

<RESERVED FOR FUTURE>

D30

<RESERVED FOR FUTURE>

D31

Config edit flag when set to a 1 it indicates end-user is currently editing the control register and we should not yet act upon set values. If 0, all bits in the control register will be evaluated and acted upon.

Data Rate/Base Rate

Function:

Indicates the current rate (speed) at which data is being transmitted on the CAN network. User applications should always specifically configure the Baud Rates for each active channel and not rely on the default values set within the BareMetal.

Type:

unsigned binary word (32-bit)

Data Range:

Lower 16 bits range is 0 - 3…​Upper 16 bits range is from 6 - 9.

Read/Write:

R/W

Operational Settings:

Upper 16 bits dedicated to data rate enumerated type value; Lower 16 bits dedicated to base rate enumerated type value.
NOTE: Data Rate is applicable only when the protocol is set to CAN FD; Base Rate is utilized by both CAN A/B and CAN FD.

Default:

0 for Base Rate;
8 for Data Rate

Data Rate (CAN FD only)

D31

D30

D29

D28

D27

D26

D25

D24

D23

D22

D21

D20

D19

D18

D17

D16

D

D

D

D

D

D

D

D

D

D

D

D

D

D

D

D

Base Rate

D15

D14

D13

D12

D11

D10

D9

D8

D7

D6

D5

D4

D3

D2

D1

D0

D

D

D

D

D

D

D

D

D

D

D

D

D

D

D

D

Valid values for Base Rate currently include:

0:

1Mb (1000K) Base Baud

1:

500K Base Baud

3:

250K Base Baud

7:

125K Base Baud

9:

83.33 Base Baud

Valid values for Data Rate currently include:

6:

4Mb (4000K) Data Baud

7:

3Mb (3000K) Data Baud

8:

2Mb (2000K) Data Baud

9:

1Mb (1000K) Data Baud

Note
Data rate of 3 Mb is not recommended as it has been found to be unreliable.

Sample Point

Function:

Indicates the sample point to be used. Different 3rd party vendor equipment may use different sample points. This register provides some flexibility to the NAI CAN FD functionality.

Type:

unsigned binary word (32-bit)

Data Range:

0 (75%) to 0x0000 0001 (80%)

Read/Write:

R/W

Operational Settings:

The sample point can be set to 75% or 80% depending on which value works best for the CAN FD operational environment

Default:

0x0000 0001 (80%)

RxMaxWorkTimeMS

Function:

Defines length of time user will wait to perform receiving of CAN FD messages before processing control is returned to all other processing.
NOTE: A value of zero forces the default value of 1000ms to be used if the Enhanced Last Error Code capabilities bit is not set in the Baremetal Capabilities register. If it is desired to spend as little time as possible, this value should be set to 0x00000001. If the Enhanced Last Error Code capabilities bit is set, the default value of 0 ms is used and is the recommended value to spend as little time as possible.

Type:

unsigned binary word (32-bit)

Data Range:

0 to 0xFFFF FFFF

Read/Write:

R/W

Operational Settings:

1000ms / 0ms

Default:

1000ms (if Enhanced Last Error Code capabilities bit is 0);
0ms (if Enhanced Last Error Code capabilities bit is 1)

TxMaxWorkTimeMS

Function:

Defines length of time user will wait to perform transmitting of CAN FD messages before processing control is returned to all other processing.
NOTE: A value of zero forces the default value of 1000ms to be used if the Enhanced Last Error Code capabilities bit is not set in the Baremetal Capabilities register. If it is desired to spend as little time as possible, this value should be set to 0x00000001. If the Enhanced Last Error Code capabilities bit is set, the default value of 0 ms is used and is the recommended value to spend as little time as possible.

Type:

unsigned binary word (32-bit)

Data Range:

0 to 0xFFFF FFFF

Read/Write:

R/W

Operational Settings:

1000ms / 0ms

Default:

1000ms (if Enhanced Last Error Code capabilities bit is 0);
0ms (if Enhanced Last Error Code capabilities bit is 1)

Transmit Enable State

Function:

Reflects the state of Transmit Enable.

Type:

unsigned binary word (32-bit)

Data Range:

0 to 0x1

Read/Write:

R/W

Operational Settings:

See below.

Default:

0

D31

D30

D29

D28

D27

D26

D25

D24

D23

D22

D21

D20

D19

D18

D17

D16

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

D15

D14

D13

D12

D11

D10

D9

D8

D7

D6

D5

D4

D3

D2

D1

D0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

D

Bit

Description

D0

Tx Enabled when bit reflects a 1

Message Status/Monitoring Registers

The registers specified in this section provide status and monitoring information on about the CAN Bus messages.

FIFO Status

Function:

Describes current FIFO Status.

Type:

unsigned binary word (32-bit)

Data Range:

NA

Read/Write:

R

Operational Settings:

See table below.

Bit

Description

Configurable?

D0

Rx FIFO EMPTY: When set to 1: Rx FIFO is empty.

No

D1

Rx FIFO ALMOST EMPTY: When set to 1: Rx FIFO is at 20% capacity.

No

D2

Rx FIFO ALMOST FULL: When set to 1: Rx FIFO is at 80% capacity.

No

D3

Rx FIFO FULL: When set to 1: Rx FIFO is full.

No

D4

Tx FIFO EMPTY: When set to 1: Tx FIFO is empty.

No

D5

Tx FIFO ALMOST EMPTY: When set to 1: Tx FIFO is at 20% capacity.

No

D6

Tx FIFO ALMOST FULL: When set to 1: Tx FIFO is at 80% capacity.

No

D7

Tx FIFO FULL: When set to 1: Tx FIFO is full.

No

Last Error Code (LEC)

Function:

Stores the value of the last detected error.
NOTE: this is a single value so if multiple errors occur prior to this register being read, only the last error value will be present.

Type:

signed binary word (32-bit) if compatibility bit D3 from BareMetal Compatibilities Registers is 0 (Non-Enhanced Error Code)
unsigned binary word (32-bit) if compatibility bit D3 from BareMetal Compatibilities Register is 1 (Enhanced Error Code)

Data Range:

0 = success; negative value = failure

Read/Write:

R/W (to allow register to be cleared)

Operational Settings:

The last error code to be received on a channel.

Default:

0

D31

D30

D29

D28

D27

D26

D25

D24

D23

D22

D21

D20

D19

D18

D17

D16

D

D

D

D

D

D

D

D

D

D

D

D

D

D

D

D

D15

D14

D13

D12

D11

D10

D9

D8

D7

D6

D5

D4

D3

D2

D1

D0

D

D

D

D

D

D

D

D

D

D

D

D

D

D

D

D

Common Error Values
(when Non-Enhanced Error Code):

-50:

INVALID_DEVICE_NUMBER

-65:

INVALID PARAMETER

-1009:

MESSAGE NOT DETECTED

Full List of Error Values when Enhanced Error Code:

(HEX)

Error Description

0x0001

NAI_BUS ERROR
Bus Errors can happen for multiple reasons. Most often are Baud Rate mismatches. Check all devices on the bus to make sure they are all running the same baud rates (both config and data for CAN FD or only config for CAN A/B). Bus Error can also take place if the bus is not properly terminated. Check the termination and/or configure the FPGA termination via the NAI SSK library functionality. Bus Errors can also happen if there is only 1 device on the bus. CAN FD needs at least 2 devices on the bus in order to function appropriately.

0x0002

NAI_SEQUENCER_START_ERROR
This error is reported if there is a problem enabling the sequencer. Sequencer can additionally be thought of as a schedule and can be configured to TX data at a desired frequency.

0x0003

NAI_SEQUENCER_STOP_ERROR
This error is reported if there is a problem stopping (or disabling) the sequencer.

0x0004

NAI_SEQUENCER_INDEX_ERROR
Sequencer index errors may occur if a sequence index that is out-of-range is attempted to be configured. Valid index range is from 1 - 31 inclusive.

0x0005

NAI_SET_DEVICE_MODE_ERROR
The BareMetal logic for CAN FD will force the CAN FD IP to be in different modes under certain circumstances (like monitor mode or normal mode). If the IP fails to enter these modes when requested, this error will be raised.

0x0006

NAI_BAUD_RATE_CHANGE_ERROR
If the CAN FD IP fails to enter the baud rate being requested, this error will be raised.

0x0007

NAI_ENABLE_FILTERS_ERROR
This error is reported if the CAN FD IP fails to enable the filters when a request is made.

0x0008

NAI_DISABLE_FILTERS_ERROR
This error is reported if the CAN FD IP fails to disable the filters when a request is made.

0x0009

NAI_MISSING_END_OF_MSG_ERROR
This error is reported if when reading a CAN message off the TX FIFO, the end of message delimiter is not found.

0x000A

NAI_INSUFFICIENT_DATA_ERROR
This error is reported when a given command (control register bit set to a 1) requires additional information, and that additional information was not found to be included. Older versions of the BareMetal code used the TX FIFO as the transfer mechanism from the user application to the BareMetal. Newer versions of the BareMetal have a separate Command FIFO that is used. In either case, if the BareMetal does not see all the information it expects on the FIFO being used, this error will be raised.

0x000B

NAI_EXPECTED_CMD_NOT_FOUND_ERROR
As discussed in the prior error regarding NAI_INSUFFICIENT_DATA_ERROR, when a control register bit is set to a 1 and the command associated with that bit requires additional information, a FIFO is used as the transport mechanism from the user application to the BareMetal application. The first piece of information the BareMetal looks for is the Command ID to make sure the data being passed on the FIFO matches the command we are looking to get additional information about. If the Command ID read off the FIFO does not match the command associated with the control register bit that we are currently processing, this error is raised.

0x000C

NAI_INIT_DEVICE_ERROR
This error is reported if the CAN FD IP fails to initialize the given CAN FD device. (Each channel of the CAN FD will have its own device ID)

0x000D

NAI_OPEN_DEVICE_ERROR
This error is reported if the CAN FD IP fails to open the given CAN FD device. (Each channel of the CAN FD will have its own device ID)

0x000E

NAI_NO_ROOM_ON_RX_FIFO_ERROR
This error is raised if when receiving a CAN message, it is determined that there is not enough room to put the entire message on the Rx FIFO. This can happen if the Rx FIFO fills up. The BareMetal will not put a partial message on the Rx FIFO. If the entire message won’t fit, the BareMetal will report this error and stop attempting to receive more CAN messages.

0x0010

NAI_FILTER_INDEX_ERROR
This error is raised if the filter index on the BareMetal side is found to be > 7. The BareMetal application expects filter index to be in the range of 0 to 7 inclusive (Max of 8 Filter Indexes).

0x0011

NAI_SET_FILTER_ERROR
This error is raised if the CAN FD IP fails to set the filter information for the specified filter index.

0x0012

NAI_GET_FILTER_ERROR
This error is raised if the CAN FD IP fails to get the filter information for the specified filter index.

0x0013

NAI_SET_FILTER_MASK_ERROR
This error is raised if the CAN FD IP fails to set the filter mask information for the specified filter mask index.

0x0014

NAI_GET_FILTER_MASK_ERROR
This error is raised if the CAN FD IP fails to get the filter mask information for the specified filter mask index.

0x0015

NAI_REMOVE_FILTER_ERROR
This error is raised if the CAN FD IP fails to remove the filter information associated with the specified filter index.

0x0020

NAI_IP_GENERAL_API_ERROR
The NAI_IP_GENERAL_API_ERROR is a general error that will be raised when internal calls into the CAN FD IP are made and return an IP failure status.

0x0021

NAI_IP_TX_FIFO_FULL
This error is raised if the CAN FD IP signals that its own Tx FIFO within the IP is full.

0x0022

NAI_IP_RX_FIFO_FULL
This error is raised if the CAN FD IP signals that its own Rx FIFO within the IP is full.

Drop Count

Function:

Every time a received message is unable to be placed onto the Rx FIFO because the FIFO is full, the message will be dropped, and this register’s value will be incremented by 1. This Drop count can be reset by sending the request to reset the drop count command via the control register (see data bit 12 (D12) of the control register description).

Type:

unsigned binary word (32-bit)

Data Range:

0 - 0xFFFF FFFF

Read/Write:

R/W

Operational Settings:

Drop Count

Default:

0

D31

D30

D29

D28

D27

D26

D25

D24

D23

D22

D21

D20

D19

D18

D17

D16

D

D

D

D

D

D

D

D

D

D

D

D

D

D

D

D

D15

D14

D13

D12

D11

D10

D9

D8

D7

D6

D5

D4

D3

D2

D1

D0

D

D

D

D

D

D

D

D

D

D

D

D

D

D

D

D

Status and Interrupt Registers

The registers may be set for any or all channels and will latch if a transition is detected on a channel or channels. Each channel(s) will remain latched until the channel is cleared. Multiple channels may be cleared simultaneously, if desired. Each channel bit in the register is polled for a read status. Any subsequent channel(s) transition, if detected, will propagate through to be read (rolling-latch).

Once the status register has been read, the act of writing a 1 back to the applicable status register to any specific bit (channel) location (bit-mapped per channel), will “clear” the bit (set the bit to 0) if the actual interruptible event condition has cleared. If the interruptible condition “event” is still persistent while clearing, this may retrigger the interrupt.

There is a corresponding Interrupt Enable and vector associated with each “Latched” Status. Each status type may be “polled” (at any time) or is “interruptible” when interrupts are enabled and the associated Interrupt Service Routine (ISR) vectors are programmed accordingly. When programmed for “interruptible” status, interrupts are typically generated and flagged with the programmed vector available as data. The host or single board computer (SBC) typically services the interrupt by a general or specific ISR, which reads the (typically) unique programmed vector (identifier of which status generated the interrupt), reads the associated status register to determine which channel in the status register was “flagged” and then “clears” the status register. This essentially resets the interrupt mechanism, which is now ready to be triggered by the next status register detected event “flag”. “Latched Status” will trigger on either “sense on edge” or “sense on level” based on the settings of the associated Set Edge/Level Interrupt register. Sense on “edge” requires a change from low to high state to trigger the status detection, while sense on “level” is independent of the previous state. Unless otherwise specified, all status or fault indications are bit set per channel.

BIT Status

There are four registers associated with the BIT Status: Dynamic, Latched, Interrupt Enable, and Set Edge/Level Interrupt

BIT Dynamic Status

BIT Latched Status

BIT Interrupt Enable

BIT Set Edge/Level Interrupt

D31

D30

D29

D28

D27

D26

D25

D24

D23

D22

D21

D20

D19

D18

D17

D16

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

D15

D14

D13

D12

D11

D10

D9

D8

D7

D6

D5

D4

D3

D2

D1

D0

0

0

0

0

0

0

0

0

Ch8

Ch7

Ch6

Ch5

Ch4

Ch3

Ch2

Ch1

BIT Dynamic Status

Function:

Indicates current condition of Built-In Test (BIT).

Type:

unsigned binary word (32-bit)

Data Range:

0 to 0x0000 00FF

Read/Write:

R

Operational Settings:

NA

Default:

0

BIT Latched Status

Function:

Sets and maintains the status of running Built-In Test (BIT), until cleared.

Type:

unsigned binary word (32-bit)

Read/Write:

R/W

Operational Settings:

Write 1 to clear register.

Default:

0

BIT Interrupt Enable

Function:

Sets the corresponding channel to enable an interrupt for whenever BIT fails for that channel.

Type:

unsigned binary word (32-bit)

Data Range:

0 to 0x0000 00FF

Read/Write:

R/W

Operational Settings:

When enabled, an interrupt will be generated whenever BIT fails for the channel. Each channel may be set for a different condition.

Default:

0

BIT Set Edge/Level Interrupt

Function:

Determines whether Interrupt Enable register will generate an interrupt for “sense on edge” or “sense on level” event detection.

Type:

unsigned binary word (32-bit)

Data Range:

0 to 0x0000 00FF

Read/Write:

R/W

Operational Settings:

Write a 1 to sense on level and a 0 to sense on edge.

Default:

Sense on edge (0)

Reset BIT

Function:

Set the bit corresponding to the channel you want to clear.

Type:

unsigned binary word (32-bit)

Data Range:

0 - 0x0000 00FF

Read/Write:

R/W

Initialized Value:

0

Operational Settings:

Set bit to 1 for channel you want to clear. Bit is self-clearing.

D31

D30

D29

D28

D27

D26

D25

D24

D23

D22

D21

D20

D19

D18

D17

D16

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

D15

D14

D13

D12

D11

D10

D9

D8

D7

D6

D5

D4

D3

D2

D1

D0

0

0

0

0

0

0

0

0

Ch8

Ch7

Ch6

Ch5

Ch4

Ch3

Ch2

Ch1

New Data Available Status

There are four registers associated with the New Data Available Status: Dynamic, Latched, Interrupt Enable, and Set Edge/Level Interrupt.

New Data Available Dynamic Status

New Data Available Latched Status

New Data Available Interrupt Enable

New Data Available Set Edge/Level Interrupt

D31

D30

D29

D28

D27

D26

D25

D24

D23

D22

D21

D20

D19

D18

D17

D16

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

D15

D14

D13

D12

D11

D10

D9

D8

D7

D6

D5

D4

D3

D2

D1

D0

0

0

0

0

0

0

0

0

Ch8

Ch7

Ch6

Ch5

Ch4

Ch3

Ch2

Ch1

New Data Available Dynamic Status

Function:

Indicates current condition of received data in Receive FIFO register.

Type:

binary word (32-bit)

Data Range:

0 to 0x0000 00FF

Read/Write:

R

Operational Settings:

NA

Default:

0

New Data Available Latched Status

Function:

Sets and maintains the status of received data in Receive FIFO register, until cleared.

Type:

binary word (32-bit)

Data Range:

0 to 0x00FF

Read/Write:

R/W

Operational Settings:

Write 1 to clear register.

Default:

0

New Data Available Interrupt Enable

Function:

Sets the corresponding channel to enable an interrupt for when CAN data is received.

Type:

binary word (32-bit)

Data Range:

0 to 0x00FF

Read/Write:

R/W

Operational Settings:

When enabled, an interrupt will be generated for each time CAN data is received in the receive FIFO. Only one interrupt vector exists for all channels. Caller must interrogate the interrupt status register to determine which channel caused the interrupt.

Default:

0

New Data Available Set Edge/Level Interrupt

Function:

Determines whether Interrupt Enable register will generate an interrupt for “sense on edge” or “sense on level” event detection.

Type:

binary word (32-bit)

Data Range:

0 to 0x00FF

Read/Write:

R/W

Operational Settings:

Write a 1 to sense on level and a 0 to sense on edge.

Default:

Sense on edge (0)

FIFO Status

There are four registers associated with the FIFO Status: Dynamic, Latched, Interrupt Enable, and Set Edge/Level Interrupt.

FIFO Dynamic Status

FIFO Latched Status

FIFO Interrupt Enable

FIFO Set Edge/Level Interrupt

D31

D30

D29

D28

D27

D26

D25

D24

D23

D22

D21

D20

D19

D18

D17

D16

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

D15

D14

D13

D12

D11

D10

D9

D8

D7

D6

D5

D4

D3

D2

D1

D0

0

0

0

0

0

0

0

0

D

D

D

D

D

D

D

D

Bit

Description

Configurable?

D0

Rx FIFO EMPTY: When set to 1: Rx FIFO is empty.

No

D1

Rx FIFO ALMOST EMPTY: When set to 1: Rx FIFO is at 20% capacity.

No

D2

Rx FIFO ALMOST FULL: When set to 1: Rx FIFO is at 80% capacity.

No

D3

Rx FIFO FULL: When set to 1: Rx FIFO is full.

No

D4

Tx FIFO EMPTY: When set to 1: Tx FIFO is empty.

No

D5

Tx FIFO ALMOST EMPTY: When set to 1: Tx FIFO is at 20% capacity.

No

D6

Tx FIFO ALMOST FULL: When set to 1: Tx FIFO is at 80% capacity.

No

D7

Tx FIFO FULL: When set to 1: Tx FIFO is full.

No

FIFO Dynamic Status

Function:

Checks the corresponding bit for a channel’s FIFO Status. The FIFO Dynamic Status register indicates the current condition of the FIFO buffer.

Type:

binary word (32-bit)

Data Range:

0 to 0x0000 00FF

Read/Write:

R

Initialized Value:

0

Operational Settings:

D0-D7 is used to show the different conditions of the buffer.

FIFO Latched Status

Function:

Checks the corresponding bit for a channel’s FIFO Status. The FIFO Latched Status register maintains the last condition of the FIFO buffer, until cleared.

Type:

binary word (32-bit)

Data Range:

0 to 0x0000 00FF

Read/Write:

R/W

Initialized Value:

0

Operational Settings:

D0-D7 is used to show the different conditions of the buffer. Write a 1 to this register to clear status.

FIFO Interrupt Enable

Function:

Interrupts may be enabled based on D0-D7 FIFO Status.

Type:

unsigned binary word (32-bit)

Data Range:

0x0000 0000 to 0x0000 00FF

Read/Write:

R/W

Initialized Value:

0 (Not Enabled)

Notes:

  • Shown below is an example of interrupts generated for the High Watermark. As shown, the interrupt is generated as the FIFO Word Count crosses the High Watermark. The interrupt will not be generated a second time until the count goes below the watermark and then above it again.

CB8 img02

FIFO Set Edge/Level Interrupt

Function:

When the FIFO Status Interrupt Enable register is enabled, this register determines whether the interrupt will be generated for either “sense on edge” or “sense on level” event detection.

Read/Write:

R/W

Initialized Value:

0

Operational Settings:

Write a 1 to sense on level and a 0 to sense on edge.

Function Register Map

KEY

Input

Output

RECEIVE REGISTERS

NOTE: Base Address - 0x4000 0000

OFFSET

REGISTER NAME

ACCESS

OFFSET

REGISTER NAME

ACCESS

0x1004

Receive FIFO Buffer Data Ch 1

R-H, W-A

0x1008

Receive FIFO Word Count Ch 1

R

0x1084

Receive FIFO Buffer Data Ch 2

R-H, W-A

0x1088

Receive FIFO Word Count Ch 2

R

0x1104

Receive FIFO Buffer Data Ch 3

R-H, W-A

0x1108

Receive FIFO Word Count Ch 3

R

0x1184

Receive FIFO Buffer Data Ch 4

R-H, W-A

0x1188

Receive FIFO Word Count Ch 4

R

0x1204

Receive FIFO Buffer Data Ch 5

R-H, W-A

0x1208

Receive FIFO Word Count Ch 5

R

0x1284

Receive FIFO Buffer Data Ch 6

R-H, W-A

0x1288

Receive FIFO Word Count Ch 6

R

0x1304

Receive FIFO Buffer Data Ch 7

R-H, W-A

0x1308

Receive FIFO Word Count Ch 7

R

0x1384

Receive FIFO Buffer Data Ch 8

R-H, W-A

0x1388

Receive FIFO Word Count Ch 8

R

NOTE: For Receive FIFO Buffer Data, 'H' is 'Host; 'A' is 'ARM'.

0x100C

Receive FIFO Frame Count Ch 1

R

0x108C

Receive FIFO Frame Count Ch 2

R

0x110C

Receive FIFO Frame Count Ch 3

R

0x118C

Receive FIFO Frame Count Ch 4

R

0x120C

Receive FIFO Frame Count Ch 5

R

0x128C

Receive FIFO Frame Count Ch 6

R

0x130C

Receive FIFO Frame Count Ch 7

R

0x138C

Receive FIFO Frame Count Ch 8

R

TRANSMIT REGISTERS

NOTE: Base Address - 0x4000 0000

OFFSET

REGISTER NAME

ACCESS

OFFSET

REGISTER NAME

ACCESS

0x1010

Transmit FIFO Buffer Data Ch 1

W-H, R-A

0x1014

Transmit FIFO Word Count Ch 1

R

0x1090

Transmit FIFO Buffer Data Ch 2

W-H, R-A

0x1094

Transmit FIFO Word Count Ch 2

R

0x1110

Transmit FIFO Buffer Data Ch 3

W-H, R-A

0x1114

Transmit FIFO Word Count Ch 3

R

0x1190

Transmit FIFO Buffer Data Ch 4

W-H, R-A

0x1194

Transmit FIFO Word Count Ch 4

R

0x1210

Transmit FIFO Buffer Data Ch 5

W-H, R-A

0x1214

Transmit FIFO Word Count Ch 5

R

0x1290

Transmit FIFO Buffer Data Ch 6

W-H, R-A

0x1294

Transmit FIFO Word Count Ch 6

R

0x1310

Transmit FIFO Buffer Data Ch 7

W-H, R-A

0x1314

Transmit FIFO Word Count Ch 7

R

0x1390

Transmit FIFO Buffer Data Ch 8

W-H, R-A

0x1394

Transmit FIFO Word Count Ch 8

R

NOTE: For Transmit FIFO Buffer Data, 'H' is 'Host; 'A' is 'ARM'.

0x1018

Transmit FIFO Frame Count Ch 1

R

0x1098

Transmit FIFO Frame Count Ch 2

R

0x1118

Transmit FIFO Frame Count Ch 3

R

0x1198

Transmit FIFO Frame Count Ch 4

R

0x1218

Transmit FIFO Frame Count Ch 5

R

0x1298

Transmit FIFO Frame Count Ch 6

R

0x1318

Transmit FIFO Frame Count Ch 7

R

0x1398

Transmit FIFO Frame Count Ch 8

R

COMMAND REGISTERS

NOTE: Base Address - 0x4000 0000

OFFSET

REGISTER NAME

ACCESS

OFFSET

REGISTER NAME

ACCESS

0x1400

BM Capabilities Register

R/W

0x1028

Command FIFO Buffer Data Ch 1

W-H, R-A

0x102C

Command FIFO Word Count Ch 1

R

0x10A8

Command FIFO Buffer Data Ch 2

W-H, R-A

0x10AC

Command FIFO Word Count Ch 2

R

0x1128

Command FIFO Buffer Data Ch 3

W-H, R-A

0x112C

Command FIFO Word Count Ch 3

R

0x11A8

Command FIFO Buffer Data Ch 4

W-H, R-A

0x11AC

Command FIFO Word Count Ch 4

R

0x1228

Command FIFO Buffer Data Ch 5

W-H, R-A

0x122C

Command FIFO Word Count Ch 5

R

0x12A8

Command FIFO Buffer Data Ch 6

W-H, R-A

0x12AC

Command FIFO Word Count Ch 6

R

0x1328

Command FIFO Buffer Data Ch 7

W-H, R-A

0x132C

Command FIFO Word Count Ch 7

R

0x13A8

Command FIFO Buffer Data Ch 8

W-H, R-A

0x13AC

Command FIFO Word Count Ch 8

R

NOTE: For Command FIFO Buffer Data, 'H' is 'Host; 'A' is 'ARM'.

CONTROL REGISTERS

NOTE: Base Address - 0x4000 0000

OFFSET

REGISTER NAME

ACCESS

OFFSET

REGISTER NAME

ACCESS

0x1000

Control Ch 1

R/W

0x101C

Data Rate/Base Rate Ch 1

R/W

0x1080

Control Ch 2

R/W

0x109C

Data Rate/Base Rate Ch 2

R/W

0x1100

Control Ch 3

R/W

0x111C

Data Rate/Base Rate Ch 3

R/W

0x1180

Control Ch 4

R/W

0x119C

Data Rate/Base Rate Ch 4

R/W

0x1200

Control Ch 5

R/W

0x121C

Data Rate/Base Rate Ch 5

R/W

0x1280

Control Ch 6

R/W

0x129C

Data Rate/Base Rate Ch 6

R/W

0x1300

Control Ch 7

R/W

0x131C

Data Rate/Base Rate Ch 7

R/W

0x1380

Control Ch 8

R/W

0x139C

Data Rate/Base Rate Ch 8

R/W

0x1020

Sample Point Ch 1

R/W

0x1060

RxMaxWorkMS Ch 1

R/W

0x10A0

Sample Point Ch 2

R/W

0x10E0

RxMaxWorkMS Ch 2

R/W

0x1120

Sample Point Ch 3

R/W

0x1160

RxMaxWorkMS Ch 3

R/W

0x11A0

Sample Point Ch 4

R/W

0x11E0

RxMaxWorkMS Ch 4

R/W

0x1220

Sample Point Ch 5

R/W

0x1260

RxMaxWorkMS Ch 5

R/W

0x12A0

Sample Point Ch 6

R/W

0x12E0

RxMaxWorkMS Ch 6

R/W

0x1320

Sample Point Ch 7

R/W

0x1360

RxMaxWorkMS Ch 7

R/W

0x13A0

Sample Point Ch 8

R/W

0x13E0

RxMaxWorkMS Ch 8

R/W

0x1064

TxMaxWorkMS Ch 1

R/W

0x1068

Tx Enable State Ch 1

R

0x10E4

TxMaxWorkMS Ch 2

R/W

0x10E8

Tx Enable State Ch 2

R

0x1164

TxMaxWorkMS Ch 3

R/W

0x1168

Tx Enable State Ch 3

R

0x11E4

TxMaxWorkMS Ch 4

R/W

0x11E8

Tx Enable State Ch 4

R

0x1264

TxMaxWorkMS Ch 5

R/W

0x1268

Tx Enable State Ch 5

R

0x12E4

TxMaxWorkMS Ch 6

R/W

0x12E8

Tx Enable State Ch 6

R

0x1364

TxMaxWorkMS Ch 7

R/W

0x1368

Tx Enable State Ch 7

R

0x13E4

TxMaxWorkMS Ch 8

R/W

0x13E8

Tx Enable State Ch 8

R

MESSAGE STATUS/MONITOR REGISTERS

NOTE: Base Address - 0x4000 0000

OFFSET

REGISTER NAME

ACCESS

OFFSET

REGISTER NAME

ACCESS

0x104C

FIFO Status Ch 1

R

0x10CC

FIFO Status Ch 2

R

0x114C

FIFO Status Ch 3

R

0x11CC

FIFO Status Ch 4

R

0x124C

FIFO Status Ch 5

R

0x12CC

FIFO Status Ch 6

R

0x134C

FIFO Status Ch 7

R

0x13CC

FIFO Status Ch 8

R

0x1024

Last Error Code Ch 1

R/W

0x1050

Drop Count Ch 1

R/W

0x10A4

Last Error Code Ch 2

R/W

0x10D0

Drop Count Ch 2

R/W

0x1124

Last Error Code Ch 3

R/W

0x1150

Drop Count Ch 3

R/W

0x11A4

Last Error Code Ch 4

R/W

0x11D0

Drop Count Ch 4

R/W

0x1224

Last Error Code Ch 5

R/W

0x1250

Drop Count Ch 5

R/W

0x12A4

Last Error Code Ch 6

R/W

0x12D0

Drop Count Ch 6

R/W

0x1324

Last Error Code Ch 7

R/W

0x1350

Drop Count Ch 7

R/W

0x13A4

Last Error Code Ch 8

R/W

0x13D0

Drop Count Ch 8

R/W

BIT REGISTER

NOTE: Base Address - 0x4000 0000

*When an event is detected, the bit associated with the event is set in this register and will remain set until the user clears the event bit. Clearing the bit requires writing a 1 back to the specific bit that was set when read (i.e. write-1-to-clear, writing a '1' to a bit set to '1' will set the bit to '0').

OFFSET

REGISTER NAME

ACCESS

OFFSET

REGISTER NAME

ACCESS

0x0800

BIT Dynamic Status

R

0x0804

BIT Latched Status*

R/W

0x0808

BIT Interrupt Enable

R/W

0x080C

BIT Set Edge/Level Interrupt

R/W

0x02B8

Reset BIT

R/W

FIFO STATUS REGISTERS

NOTE: Base Address - 0x4000 0000

*When an event is detected, the bit associated with the event is set in this register and will remain set until the user clears the event bit. Clearing the bit requires writing a 1 back to the specific bit that was set when read (i.e. write-1-to-clear, writing a '1' to a bit set to '1' will set the bit to '0').

OFFSET

REGISTER NAME

ACCESS

OFFSET

REGISTER NAME

ACCESS

0x0810

Dynamic Status Ch 1

R

0x0820

Dynamic Status Ch 2

R

0x0814

Latched Status Ch 1*

R/W

0x0824

Latched Status Ch 2*

R/W

0x0818

Interrupt Enable Ch 1

R/W

0x0828

Interrupt Enable Ch 2

R/W

0x081C

Set Edge/Level Interrupt Ch 1

R/W

0x082C

Set Edge/Level Interrupt Ch 2

R/W

0x0830

Dynamic Status Ch 3

R

0x0840

Dynamic Status Ch 4

R

0x0834

Latched Status Ch 3*

R/W

0x0844

Latched Status Ch 4*

R/W

0x0838

Interrupt Enable Ch 3

R/W

0x0848

Interrupt Enable Ch 4

R/W

0x083C

Set Edge/Level Interrupt Ch 3

R/W

0x084C

Set Edge/Level Interrupt Ch 4

R/W

0x0850

Dynamic Status Ch 5

R

0x0860

Dynamic Status Ch 6

R

0x0854

Latched Status Ch 5*

R/W

0x0864

Latched Status Ch 6*

R/W

0x0858

Interrupt Enable Ch 5

R/W

0x0868

Interrupt Enable Ch 6

R/W

0x085C

Set Edge/Level Interrupt Ch 5

R/W

0x086C

Set Edge/Level Interrupt Ch 6

R/W

0x0870

Dynamic Status Ch 7

R

0x0880

Dynamic Status Ch 8

R

0x0874

Latched Status Ch 7*

R/W

0x0884

Latched Status Ch 8*

R/W

0x0878

Interrupt Enable Ch 7

R/W

0x0888

Interrupt Enable Ch 8

R/W

0x087C

Set Edge/Level Interrupt Ch 7

R/W

0x088C

Set Edge/Level Interrupt Ch 8

R/W

NEW DATA AVAILABLE REGISTER

NOTE: Base Address - 0x4000 0000

OFFSET

REGISTER NAME

ACCESS

OFFSET

REGISTER NAME

ACCESS

0x0890

Dynamic Status Ch 1-8

R

0x0894

Latched Status Ch 1-8*

R/W

0x0898

Interrupt Enable Ch 1-8

R/W

0x089C

Set Edge/Level Interrupt Ch 1-8

R/W

RESPONSE REGISTERS

When data other than CAN messages needs to be returned from the CAN module, the data to be returned is placed in a series of Response Registers. Each channel has its own series of Response Registers that can be used. The BareMetal logic will fill these registers and update the Response Count so the consumer can determine how many of the Response Registers need to be read.

NOTE: Base Address - 0x4000 0000

OFFSET

REGISTER NAME

ACCESS

OFFSET

REGISTER NAME

ACCESS

0x1500

Response Count Ch 1

R

0x1580

Response Count Ch 2

R

0x1504

Response Data Ch 1

R

0x1584

Response Data Ch 2

R

0x1508

Response Data Ch 1

R

0x1588

Response Data Ch 2

R

0x150C

Response Data Ch 1

R

0x158C

Response Data Ch 2

R

…​

…​

0x157C

Response Data Ch 1

R

0x15FC

Response Data Ch 2

R

0x1600

Response Count Ch 3

R

0x1680

Response Count Ch 4

R

0x1604

Response Data Ch 3

R

0x1684

Response Data Ch 4

R

0x1608

Response Data Ch 3

R

0x1688

Response Data Ch 4

R

0x160C

Response Data Ch 3

R

0x168C

Response Data Ch 4

R

…​

…​

0x167C

Response Data Ch 3

R

0x16FC

Response Data Ch 4

R

0x1700

Response Count Ch 5

R

0x1780

Response Count Ch 6

R

0x1704

Response Data Ch 5

R

0x1784

Response Data Ch 6

R

0x1708

Response Data Ch 5

R

0x1788

Response Data Ch 6

R

0x170C

Response Data Ch 5

R

0x178C

Response Data Ch 6

R

…​

…​

0x177C

Response Data Ch 5

R

0x17FC

Response Data Ch 6

R

0x1800

Response Count Ch 7

R

0x1880

Response Count Ch 8

R

0x1804

Response Data Ch 7

R

0x1884

Response Data Ch 8

R

0x1808

Response Data Ch 7

R

0x1888

Response Data Ch 8

R

0x180C

Response Data Ch 7

R

0x188C

Response Data Ch 8

R

…​

…​

0x187C

Response Data Ch 7

R

0x18FC

Response Data Ch 8

R

APPENDIX: PIN-OUT DETAILS

Pin-out details (for reference) are shown below, with respect to DATAIO. Additional information on pin-outs can be found in the Motherboard Operational Manuals.

Module Signal
(Ref Only)

44-Pin I/O

50-Pin I/O (Mod Slot 1-J3)

50-Pin I/O (Mod Slot 2-J4)

50-Pin I/O (Mod Slot 3-J3)

50-Pin I/O (Mod Slot 3-J4)

CAN 2.0 A/B,
ARINC 825-4,
FD

DATIO1

2

10

1

2

CANH-CH1

DATIO2

24

35

26

27

CANL-CH1

DATIO3

3

11

2

3

CANH-CH2

DATIO4

25

36

27

28

CANL-CH2

DATIO5

5

13

4

5

ISO_GND_CH2

DATIO6

27

38

29

30

ISO_GND_CH1

DATIO7

7

14

5

6

CANH-CH3

DATIO8

29

39

30

31

CANL-CH3

DATIO9

8

15

6

7

CANH-CH4

DATIO10

30

40

31

32

CANL-CH4

DATIO11

10

17

8

9

ISO_GND_CH3

DATIO12

32

42

33

34

ISO_GND_CH4

DATIO13

12

18

9

17

CANH-CH5

DATIO14

34

43

34

42

CANL-CH5

DATIO15

13

19

10

18

CANH-CH6

DATIO16

35

44

35

43

CANL-CH6

DATIO17

15

44

35

43

ISO_GND_CH6

DATIO18

37

46

37

45

ISO_GND_CH5

DATIO19

17

22

13

21

CANH-CH7

DATIO20

39

47

38

46

CANL-CH7

DATIO21

18

23

14

22

CANH-CH8

DATIO22

40

48

39

47

CANL-CH8

DATIO23

20

25

16

24

ISO_GND_CH8

DATIO24

42

50

41

49

ISO_GND_CH7

DATIO25

4

12

3

4

DATIO26

26

37

28

29

DATIO27

9

16

7

8

DATIO28

31

41

32

33

DATIO29

14

20

11

19

DATIO30

36

45

36

44

DATIO31

19

24

15

23

DATIO32

41

49

40

48

DATIO33

6

DATIO34

28

DATIO35

11

DATIO36

33

DATIO37

16

DATIO38

38

DATIO39

21

DATIO40

43

N/A

DOCS.NAII REVISIONS

Revision Date

Description

2026-03-10

Initial release of CB8 manual.

STATUS AND INTERRUPTS

Status registers indicate the detection of faults or events. The status registers can be channel bit-mapped or event bit-mapped. An example of a channel bit-mapped register is the BIT status register, and an example of an event bit-mapped register is the FIFO status register.

For those status registers that allow interrupts to be generated upon the detection of the fault or the event, there are four registers associated with each status: Dynamic, Latched, Interrupt Enabled, and Set Edge/Level Interrupt.

Dynamic Status: The Dynamic Status register indicates the current condition of the fault or the event. If the fault or the event is momentary, the contents in this register will be clear when the fault or the event goes away. The Dynamic Status register can be polled, however, if the fault or the event is sporadic, it is possible for the indication of the fault or the event to be missed.

Latched Status: The Latched Status register indicates whether the fault or the event has occurred and keeps the state until it is cleared by the user. Reading the Latched Status register is a better alternative to polling the Dynamic Status register because the contents of this register will not clear until the user commands to clear the specific bit(s) associated with the fault or the event in the Latched Status register. Once the status register has been read, the act of writing a 1 back to the applicable status register to any specific bit (channel/event) location will “clear” the bit (set the bit to 0). When clearing the channel/event bits, it is strongly recommended to write back the same bit pattern as read from the Latched Status register. For example, if the channel bit-mapped Latched Status register contains the value 0x0000 0005, which indicates fault/event detection on channel 1 and 3, write the value 0x0000 0005 to the Latched Status register to clear the fault/event status for channel 1 and 3. Writing a “1” to other channels that are not set (example 0x0000 000F) may result in incorrectly “clearing” incoming faults/events for those channels (example, channel 2 and 4).

Interrupt Enable: If interrupts are preferred upon the detection of a fault or an event, enable the specific channel/event interrupt in the Interrupt Enable register. The bits in Interrupt Enable register map to the same bits in the Latched Status register. When a fault or event occurs, an interrupt will be fired. Subsequent interrupts will not trigger until the application acknowledges the fired interrupt by clearing the associated channel/event bit in the Latched Status register. If the interruptible condition is still persistent after clearing the bit, this may retrigger the interrupt depending on the Edge/Level setting.

Set Edge/Level Interrupt: When interrupts are enabled, the condition on retriggering the interrupt after the Latch Register is “cleared” can be specified as “edge” triggered or “level” triggered. Note, the Edge/Level Trigger also affects how the Latched Register value is adjusted after it is “cleared” (see below).

  • Edge triggered: An interrupt will be retriggered when the Latched Status register change from low (0) to high (1) state. Uses for edge-triggered interrupts would include transition detections (Low-to-High transitions, High-to-Low transitions) or fault detections. After “clearing” an interrupt, another interrupt will not occur until the next transition or the re-occurrence of the fault again.

  • Level triggered: An interrupt will be generated when the Latched Status register remains at the high (1) state. Level-triggered interrupts are used to indicate that something needs attention.

Interrupt Vector and Steering

When interrupts are enabled, the interrupt vector associated with the specific interrupt can be programmed with a unique number/identifier defined by the user such that it can be utilized in the Interrupt Service Routine (ISR) to identify the type of interrupt. When an interrupt occurs, the contents of the Interrupt Vector registers is reported as part of the interrupt mechanism. In addition to specifying the interrupt vector, the interrupt can be directed (“steered”) to the native bus or to the application running on the onboard ARM processor.

Interrupt Trigger Types

In most applications, limiting the number of interrupts generated is preferred as interrupts are costly, thus choosing the correct Edge/Level interrupt trigger to use is important.

Example 1: Fault detection

This example illustrates interrupt considerations when detecting a fault like an “open” on a line. When an “open” is detected, the system will receive an interrupt. If the “open” on the line is persistent and the trigger is set to “edge”, upon “clearing” the interrupt, the system will not regenerate another interrupt. If, instead, the trigger is set to “level”, upon “clearing” the interrupt, the system will re-generate another interrupt. Thus, in this case, it will be better to set the trigger type to “edge”.

Example 2: Threshold detection

This example illustrates interrupt considerations when detecting an event like reaching or exceeding the “high watermark” threshold value. In a communication device, when the number of elements received in the FIFO reaches the high-watermark threshold, an interrupt will be generated. Normally, the application would read the count of the number of elements in the FIFO and read this number of elements from the FIFO. After reading the FIFO data, the application would “clear” the interrupt. If the trigger type is set to “edge”, another interrupt will be generated only if the number of elements in FIFO goes below the “high watermark” after the “clearing” the interrupt and then fills up to reach the “high watermark” threshold value. Since receiving communication data is inherently asynchronous, it is possible that data can continue to fill the FIFO as the application is pulling data off the FIFO. If, at the time the interrupt is “cleared”, the number of elements in the FIFO is at or above the “high watermark”, no interrupts will be generated. In this case, it will be better to set the trigger type to “level”, as the purpose here is to make sure that the FIFO is serviced when the number of elements exceeds the high watermark threshold value. Thus, upon “clearing” the interrupt, if the number of elements in the FIFO is at or above the “high watermark” threshold value, another interrupt will be generated indicating that the FIFO needs to be serviced.

Dynamic and Latched Status Registers Examples

The examples in this section illustrate the differences in behavior of the Dynamic Status and Latched Status registers as well as the differences in behavior of Edge/Level Trigger when the Latched Status register is cleared.

Status and Interrupts Fig1

Figure 1. Example of Module’s Channel-Mapped Dynamic and Latched Status States

No Clearing of Latched Status Clearing of Latched Status (Edge-Triggered) Clearing of Latched Status(Level-Triggered)

Time

Dynamic Status

Latched Status

Action

Latched Status

Action

Latched

T0

0x0

0x0

Read Latched Register

0x0

Read Latched Register

0x0

T1

0x1

0x1

Read Latched Register

0x1

0x1

T1

0x1

0x1

Write 0x1 to Latched Register

Write 0x1 to Latched Register

T1

0x1

0x1

0x0

0x1

T2

0x0

0x1

Read Latched Register

0x0

Read Latched Register

0x1

T2

0x0

0x1

Read Latched Register

0x0

Write 0x1 to Latched Register

T2

0x0

0x1

Read Latched Register

0x0

0x0

T3

0x2

0x3

Read Latched Register

0x2

Read Latched Register

0x2

T3

0x2

0x3

Write 0x2 to Latched Register

Write 0x2 to Latched Register

T3

0x2

0x3

0x0

0x2

T4

0x2

0x3

Read Latched Register

0x1

Read Latched Register

0x3

T4

0x2

0x3

Write 0x1 to Latched Register

Write 0x3 to Latched Register

T4

0x2

0x3

0x0

0x2

T5

0xC

0xF

Read Latched Register

0xC

Read Latched Register

0xE

T5

0xC

0xF

Write 0xC to Latched Register

Write 0xE to Latched Register

T5

0xC

0xF

0x0

0xC

T6

0xC

0xF

Read Latched Register

0x0

Read Latched

0xC

T6

0xC

0xF

Read Latched Register

0x0

Write 0xC to Latched Register

T6

0xC

0xF

Read Latched Register

0x0

0xC

T7

0x4

0xF

Read Latched Register

0x0

Read Latched Register

0xC

T7

0x4

0xF

Read Latched Register

0x0

Write 0xC to Latched Register

T7

0x4

0xF

Read Latched Register

0x0

0x4

T8

0x4

0xF

Read Latched Register

0x0

Read Latched Register

0x4

Interrupt Examples

The examples in this section illustrate the interrupt behavior with Edge/Level Trigger.

Status and Interrupts Fig2

Figure 2. Illustration of Latched Status State for Module with 4-Channels with Interrupt Enabled

Time

Latched Status (Edge-Triggered - Clear Multi-Channel)

Latched Status (Edge-Triggered - Clear Single Channel)

Latched Status (Level-Triggered - Clear Multi-Channel)

Action

Latched

Action

Latched

Action

Latched

T1 (Int 1)

Interrupt Generated Read Latched Registers

0x1

Interrupt Generated Read Latched Registers

0x1

Interrupt Generated Read Latched Registers

0x1

T1 (Int 1)

Write 0x1 to Latched Register

Write 0x1 to Latched Register

Write 0x1 to Latched Register

T1 (Int 1)

0x0

0x0

Interrupt re-triggers Note, interrupt re-triggers after each clear until T2.

0x1

T3 (Int 2)

Interrupt Generated Read Latched Registers

0x2

Interrupt Generated Read Latched Registers

0x2

Interrupt Generated Read Latched Registers

0x2

T3 (Int 2)

Write 0x2 to Latched Register

Write 0x2 to Latched Register

Write 0x2 to Latched Register

T3 (Int 2)

0x0

0x0

Interrupt re-triggers Note, interrupt re-triggers after each clear until T7.

0x2

T4 (Int 3)

Interrupt Generated Read Latched Registers

0x1

Interrupt Generated Read Latched Registers

0x1

Interrupt Generated Read Latched Registers

0x3

T4 (Int 3)

Write 0x1 to Latched Register

Write 0x1 to Latched Register

Write 0x3 to Latched Register

T4 (Int 3)

0x0

0x0

Interrupt re-triggers Note, interrupt re-triggers after each clear and 0x3 is reported in Latched Register until T5.

0x3

T4 (Int 3)

0x0

0x0

Interrupt re-triggers Note, interrupt re-triggers after each clear until T7.

0x2

T6 (Int 4)

Interrupt Generated Read Latched Registers

0xC

Interrupt Generated Read Latched Registers

0xC

Interrupt Generated Read Latched Registers

0xE

T6 (Int 4)

Write 0xC to Latched Register

Write 0x4 to Latched Register

Write 0xE to Latched Register

T6 (Int 4)

0x0

Interrupt re-triggers Write 0x8 to Latched Register

0x8

Interrupt re-triggers Note, interrupt re-triggers after each clear and 0xE is reported in Latched Register until T7.

0xE

T6 (Int 4)

0x0

0x0

Interrupt re-triggers Note, interrupt re-triggers after each clear and 0xC is reported in Latched Register until T8.

0xC

T6 (Int 4)

0x0

0x0

Interrupt re-triggers Note, interrupt re-triggers after each clear and 0x4 is reported in Latched Register always.

0x4

REVISION HISTORY

Motherboard Manual - Status and Interrupts Revision History

Revision

Revision Date

Description

C

2021-11-30

C08896; Transition manual to docbuilder format - no technical info change.

DOCS.NAII REVISIONS

Revision Date

Description

2026-03-02

Formatting updates to document; no technical changes.

MODULE COMMON REGISTERS

The registers described in this document are common to all NAI Generation 5 modules.

Module Information Registers

The registers in this section provide module information such as firmware revisions, capabilities and unique serial number information.

FPGA Version Registers

The FPGA firmware version registers include registers that contain the Revision, Compile Timestamp, SerDes Revision, Template Revision and Zynq Block Revision information.

FPGA Revision

Function:

FPGA firmware revision

Type:

unsigned binary word (32-bit)

Data Range:

0x0000 0000 to 0xFFFF FFFF

Read/Write:

R

Initialized Value:

Value corresponding to the revision of the board’s FPGA

Operational Settings:

The upper 16-bits are the major revision and the lower 16-bits are the minor revision.

D31

D30

D29

D28

D27

D26

D25

D24

D23

D22

D21

D20

D19

D18

D17

D16

Major Revision Number

D15

D14

D13

D12

D11

D10

D9

D8

D7

D6

D5

D4

D3

D2

D1

D0

Minor Revision Number

FPGA Compile Timestamp

Function:

Compile Timestamp for the FPGA firmware.

Type:

unsigned binary word (32-bit)

Data Range:

N/A

Read/Write:

R

Initialized Value:

Value corresponding to the compile timestamp of the board’s FPGA

Operational Settings:

The 32-bit value represents the Day, Month, Year, Hour, Minutes and Seconds as formatted in the table:

D31

D30

D29

D28

D27

D26

D25

D24

D23

D22

D21

D20

D19

D18

D17

D16

day (5-bits)

month (4-bits)

year (6-bits)

hr

D15

D14

D13

D12

D11

D10

D9

D8

D7

D6

D5

D4

D3

D2

D1

D0

hour (5-bits)

minutes (6-bits)

seconds (6-bits)

FPGA SerDes Revision

Function:

FPGA SerDes revision

Type:

unsigned binary word (32-bit)

Data Range:

0x0000 0000 to 0xFFFF FFFF

Read/Write:

R

Initialized Value:

Value corresponding to the SerDes revision of the board’s FPGA

Operational Settings:

The upper 16-bits are the major revision, and the lower 16-bits are the minor revision.

D31

D30

D29

D28

D27

D26

D25

D24

D23

D22

D21

D20

D19

D18

D17

D16

Major Revision Number

D15

D14

D13

D12

D11

D10

D9

D8

D7

D6

D5

D4

D3

D2

D1

D0

Minor Revision Number

FPGA Template Revision

Function:

FPGA Template revision

Type:

unsigned binary word (32-bit)

Data Range:

0x0000 0000 to 0xFFFF FFFF

Read/Write:

R

Initialized Value:

Value corresponding to the template revision of the board’s FPGA

Operational Settings:

The upper 16-bits are the major revision, and the lower 16-bits are the minor revision.

D31

D30

D29

D28

D27

D26

D25

D24

D23

D22

D21

D20

D19

D18

D17

D16

Major Revision Number

D15

D14

D13

D12

D11

D10

D9

D8

D7

D6

D5

D4

D3

D2

D1

D0

Minor Revision Number

FPGA Zynq Block Revision

Function:

FPGA Zynq Block revision

Type:

unsigned binary word (32-bit)

Data Range:

0x0000 0000 to 0xFFFF FFFF

Read/Write:

R

Initialized Value:

Value corresponding to the Zynq block revision of the board’s FPGA

Operational Settings:

The upper 16-bits are the major revision, and the lower 16-bits are the minor revision.

D31

D30

D29

D28

D27

D26

D25

D24

D23

D22

D21

D20

D19

D18

D17

D16

Major Revision Number

D15

D14

D13

D12

D11

D10

D9

D8

D7

D6

D5

D4

D3

D2

D1

D0

Minor Revision Number

Bare Metal Version Registers

The Bare Metal firmware version registers include registers that contain the Revision and Compile Time information.

Bare Metal Revision

Function:

Bare Metal firmware revision

Type:

unsigned binary word (32-bit)

Data Range:

0x0000 0000 to 0xFFFF FFFF

Read/Write:

R

Initialized Value:

Value corresponding to the revision of the board’s Bare Metal

Operational Settings:

The upper 16-bits are the major revision and the lower 16-bits are the minor revision.

D31

D30

D29

D28

D27

D26

D25

D24

D23

D22

D21

D20

D19

D18

D17

D16

Major Revision Number

D15

D14

D13

D12

D11

D10

D9

D8

D7

D6

D5

D4

D3

D2

D1

D0

Minor Revision Number

Bare Metal Compile Time

Function:

Provides an ASCII representation of the Date/Time for the Bare Metal compile time.

Type:

24-character ASCII string - Six (6) unsigned binary word (32-bit)

Data Range:

N/A

Read/Write:

R

Initialized Value:

Value corresponding to the ASCII representation of the compile time of the board’s Bare Metal

Operational Settings:

The six 32-bit words provide an ASCII representation of the Date/Time. The hexadecimal values in the field below represent: May 17 2019 at 15:38:32

Note
little-endian order of ASCII values

Word 1 (Ex. 0x2079614D)

D31

D30

D29

D28

D27

D26

D25

D24

D23

D22

D21

D20

D19

D18

D17

D16

Space (0x20)

Month ('y' - 0x79)

D15

D14

D13

D12

D11

D10

D9

D8

D7

D6

D5

D4

D3

D2

D1

D0

Month ('a' - 0x61)

Month ('M' - 0x4D)

Word 2 (Ex. 0x32203731)

D31

D30

D29

D28

D27

D26

D25

D24

D23

D22

D21

D20

D19

D18

D17

D16

Year ('2' - 0x32)

Space (0x20)

D15

D14

D13

D12

D11

D10

D9

D8

D7

D6

D5

D4

D3

D2

D1

D0

Day ('7' - 0x37)

Day ('1' - 0x31)

Word 3 (Ex. 0x20393130)

D31

D30

D29

D28

D27

D26

D25

D24

D23

D22

D21

D20

D19

D18

D17

D16

Space (0x20)

Year ('9' - 0x39)

D15

D14

D13

D12

D11

D10

D9

D8

D7

D6

D5

D4

D3

D2

D1

D0

Year ('1' - 0x31)

Year ('0' - 0x30)

Word 4 (Ex. 0x31207461)

D31

D30

D29

D28

D27

D26

D25

D24

D23

D22

D21

D20

D19

D18

D17

D16

Hour ('1' - 0x31)

Space (0x20)

D15

D14

D13

D12

D11

D10

D9

D8

D7

D6

D5

D4

D3

D2

D1

D0

'a' (0x74)

't' (0x61)

Word 5 (Ex. 0x38333A35)

D31

D30

D29

D28

D27

D26

D25

D24

D23

D22

D21

D20

D19

D18

D17

D16

Minute ('8' - 0x38)

Minute ('3' - 0x33)

D15

D14

D13

D12

D11

D10

D9

D8

D7

D6

D5

D4

D3

D2

D1

D0

':' (0x3A)

Hour ('5' - 0x35)

Word 6 (Ex. 0x0032333A)

D31

D30

D29

D28

D27

D26

D25

D24

D23

D22

D21

D20

D19

D18

D17

D16

NULL (0x00)

Seconds ('2' - 0x32)

D15

D14

D13

D12

D11

D10

D9

D8

D7

D6

D5

D4

D3

D2

D1

D0

Seconds ('3' - 0x33)

':' (0x3A)

FSBL Version Registers

The FSBL version registers include registers that contain the Revision and Compile Time information for the First Stage Boot Loader (FSBL).

FSBL Revision

Function:

FSBL firmware revision

Type:

unsigned binary word (32-bit)

Data Range:

0x0000 0000 to 0xFFFF FFFF

Read/Write:

R

Initialized Value:

Value corresponding to the revision of the board’s FSBL

Operational Settings:

The upper 16-bits are the major revision, and the lower 16-bits are the minor revision.

D31

D30

D29

D28

D27

D26

D25

D24

D23

D22

D21

D20

D19

D18

D17

D16

Major Revision Number

D15

D14

D13

D12

D11

D10

D9

D8

D7

D6

D5

D4

D3

D2

D1

D0

Minor Revision Number

FSBL Compile Time

Function:

Provides an ASCII representation of the Date/Time for the FSBL compile time.

Type:

24-character ASCII string - Six (6) unsigned binary word (32-bit)

Data Range:

N/A

Read/Write:

R

Initialized Value:

Value corresponding to the ASCII representation of the Compile Time of the board’s FSBL

Operational Settings:

The six 32-bit words provide an ASCII representation of the Date/Time.

The hexadecimal values in the field below represent: May 17 2019 at 15:38:32

Note
little-endian order of ASCII values

Word 1 (Ex. 0x2079614D)

D31

D30

D29

D28

D27

D26

D25

D24

D23

D22

D21

D20

D19

D18

D17

D16

Space (0x20)

Month ('y' - 0x79)

D15

D14

D13

D12

D11

D10

D9

D8

D7

D6

D5

D4

D3

D2

D1

D0

Month ('a' - 0x61)

Month ('M' - 0x4D)

Word 2 (Ex. 0x32203731)

D31

D30

D29

D28

D27

D26

D25

D24

D23

D22

D21

D20

D19

D18

D17

D16

Year ('2' - 0x32)

Space (0x20)

D15

D14

D13

D12

D11

D10

D9

D8

D7

D6

D5

D4

D3

D2

D1

D0

Day ('7' - 0x37)

Day ('1' - 0x31)

Word 3 (Ex. 0x20393130)

D31

D30

D29

D28

D27

D26

D25

D24

D23

D22

D21

D20

D19

D18

D17

D16

Space (0x20)

Year ('9' - 0x39)

D15

D14

D13

D12

D11

D10

D9

D8

D7

D6

D5

D4

D3

D2

D1

D0

Year ('1' - 0x31)

Year ('0' - 0x30)

Word 4 (Ex. 0x31207461)

D31

D30

D29

D28

D27

D26

D25

D24

D23

D22

D21

D20

D19

D18

D17

D16

Hour ('1' - 0x31)

Space (0x20)

D15

D14

D13

D12

D11

D10

D9

D8

D7

D6

D5

D4

D3

D2

D1

D0

'a' (0x74)

't' (0x61)

Word 5 (Ex. 0x38333A35)

D31

D30

D29

D28

D27

D26

D25

D24

D23

D22

D21

D20

D19

D18

D17

D16

Minute ('8' - 0x38)

Minute ('3' - 0x33)

D15

D14

D13

D12

D11

D10

D9

D8

D7

D6

D5

D4

D3

D2

D1

D0

':' (0x3A)

Hour ('5' - 0x35)

Word 6 (Ex. 0x0032333A)

D31

D30

D29

D28

D27

D26

D25

D24

D23

D22

D21

D20

D19

D18

D17

D16

NULL (0x00)

Seconds ('2' - 0x32)

D15

D14

D13

D12

D11

D10

D9

D8

D7

D6

D5

D4

D3

D2

D1

D0

Seconds ('3' - 0x33)

':' (0x3A)

Module Serial Number Registers

The Module Serial Number registers include registers that contain the Serial Numbers for the Interface Board and the Functional Board of the module.

Interface Board Serial Number

Function:

Unique 128-bit identifier used to identify the interface board.

Type:

16-character ASCII string - Four (4) unsigned binary words (32-bit)

Data Range:

N/A

Read/Write:

R

Initialized Value:

Serial number of the interface board

Operational Settings:

This register is for information purposes only.

Functional Board Serial Number

Function:

Unique 128-bit identifier used to identify the functional board.

Type:

16-character ASCII string - Four (4) unsigned binary words (32-bit)

Data Range:

N/A

Read/Write:

R

Initialized Value:

Serial number of the functional board

Operational Settings:

This register is for information purposes only.

Module Capability

Function:

Provides indication for whether or not the module can support the following: SerDes block reads, SerDes FIFO block reads, SerDes packing (combining two 16-bit values into one 32-bit value) and floating point representation. The purpose for block access and packing is to improve the performance of accessing larger amounts of data over the SerDes interface.

Type:

unsigned binary word (32-bit)

Data Range:

0x0000 0000 to 0x0000 0107

Read/Write:

R

Initialized Value:

0x0000 0107

Operational Settings:

A “1” in the bit associated with the capability indicates that it is supported.

D31

D30

D29

D28

D27

D26

D25

D24

D23

D22

D21

D20

D19

D18

D17

D16

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

D15

D14

D13

D12

D11

D10

D9

D8

D7

D6

D5

D4

D3

D2

D1

D0

0

0

0

0

0

0

0

Flt-Pt

0

0

0

0

0

Pack

FIFO Blk

Blk

Module Memory Map Revision

Function:

Module Memory Map revision

Type:

unsigned binary word (32-bit)

Data Range:

0x0000 0000 to 0xFFFF FFFF

Read/Write:

R

Initialized Value:

Value corresponding to the Module Memory Map Revision

Operational Settings:

The upper 16-bits are the major revision and the lower 16-bits are the minor revision.

D31

D30

D29

D28

D27

D26

D25

D24

D23

D22

D21

D20

D19

D18

D17

D16

Major Revision Number

D15

D14

D13

D12

D11

D10

D9

D8

D7

D6

D5

D4

D3

D2

D1

D0

Minor Revision Number

Module Measurement Registers

The registers in this section provide module temperature measurement information.

Temperature Readings Registers

The temperature registers provide the current, maximum (from power-up) and minimum (from power-up) Zynq and PCB temperatures.

Interface Board Current Temperature

Function:

Measured PCB and Zynq Core temperatures on Interface Board.

Type:

signed byte (8-bits) for PCB and signed byte (8-bits) for Zynq core temperatures

Data Range:

0x0000 0000 to 0x0000 FFFF

Read/Write:

R

Initialized Value:

Value corresponding to the measured PCB and Zynq core temperatures based on the table below

Operational Settings:

The upper 16-bits are not used, and the lower 16-bits are the PCB and Zynq Core Temperatures. For example, if the register contains the value 0x0000 202C, this represents PCB Temperature = 32° Celsius and Zynq Temperature = 44° Celsius.

D31

D30

D29

D28

D27

D26

D25

D24

D23

D22

D21

D20

D19

D18

D17

D16

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

D15

D14

D13

D12

D11

D10

D9

D8

D7

D6

D5

D4

D3

D2

D1

D0

PCB Temperature

Zynq Core Temperature

Functional Board Current Temperature

Function:

Measured PCB temperature on Functional Board.

Type:

signed byte (8-bits) for PCB

Data Range:

0x0000 0000 to 0x0000 00FF

Read/Write:

R

Initialized Value:

Value corresponding to the measured PCB on the table below

Operational Settings:

The upper 24-bits are not used, and the lower 8-bits are the PCB Temperature. For example, if the register contains the value 0x0000 0019, this represents PCB Temperature = 25° Celsius.

D31

D30

D29

D28

D27

D26

D25

D24

D23

D22

D21

D20

D19

D18

D17

D16

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

D15

D14

D13

D12

D11

D10

D9

D8

D7

D6

D5

D4

D3

D2

D1

D0

0

0

0

0

0

0

0

0

PCB Temperature

Interface Board Maximum Temperature

Function:

Maximum PCB and Zynq Core temperatures on Interface Board since power-on.

Type:

signed byte (8-bits) for PCB and signed byte (8-bits) for Zynq core temperatures

Data Range:

0x0000 0000 to 0x0000 FFFF

Read/Write:

R

Initialized Value:

Value corresponding to the maximum measured PCB and Zynq core temperatures since power-on based on the table below

Operational Settings:

The upper 16-bits are not used, and the lower 16-bits are the maximum PCB and Zynq Core Temperatures. For example, if the register contains the value 0x0000 5569, this represents maximum PCB Temperature = 85° Celsius and maximum Zynq Temperature = 105° Celsius.

D31

D30

D29

D28

D27

D26

D25

D24

D23

D22

D21

D20

D19

D18

D17

D16

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

D15

D14

D13

D12

D11

D10

D9

D8

D7

D6

D5

D4

D3

D2

D1

D0

PCB Temperature

Zynq Core Temperature

Interface Board Minimum Temperature

Function:

Minimum PCB and Zynq Core temperatures on Interface Board since power-on.

Type:

signed byte (8-bits) for PCB and signed byte (8-bits) for Zynq core temperatures

Data Range:

0x0000 0000 to 0x0000 FFFF

Read/Write:

R

Initialized Value:

Value corresponding to the minimum measured PCB and Zynq core temperatures since power-on based on the table below

Operational Settings:

The upper 16-bits are not used, and the lower 16-bits are the minimum PCB and Zynq Core Temperatures. For example, if the register contains the value 0x0000 D8E7, this represents minimum PCB Temperature = -40° Celsius and minimum Zynq Temperature = -25° Celsius.

D31

D30

D29

D28

D27

D26

D25

D24

D23

D22

D21

D20

D19

D18

D17

D16

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

D15

D14

D13

D12

D11

D10

D9

D8

D7

D6

D5

D4

D3

D2

D1

D0

PCB Temperature

Zynq Core Temperature

Functional Board Maximum Temperature

Function:

Maximum PCB temperature on Functional Board since power-on.

Type:

signed byte (8-bits) for PCB

Data Range:

0x0000 0000 to 0x0000 00FF

Read/Write:

R

Initialized Value:

Value corresponding to the measured PCB on the table below

Operational Settings:

The upper 24-bits are not used, and the lower 8-bits are the PCB Temperature. For example, if the register contains the value 0x0000 0055, this represents PCB Temperature = 85° Celsius.

D31

D30

D29

D28

D27

D26

D25

D24

D23

D22

D21

D20

D19

D18

D17

D16

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

D15

D14

D13

D12

D11

D10

D9

D8

D7

D6

D5

D4

D3

D2

D1

D0

0

0

0

0

0

0

0

0

PCB Temperature

Functional Board Minimum Temperature

Function:

Minimum PCB temperature on Functional Board since power-on.

Type:

signed byte (8-bits) for PCB

Data Range:

0x0000 0000 to 0x0000 00FF

Read/Write:

R

Initialized Value:

Value corresponding to the measured PCB on the table below

Operational Settings:

The upper 24-bits are not used, and the lower 8-bits are the PCB Temperature. For example, if the register contains the value 0x0000 00D8, this represents PCB Temperature = -40° Celsius.

D31

D30

D29

D28

D27

D26

D25

D24

D23

D22

D21

D20

D19

D18

D17

D16

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

D15

D14

D13

D12

D11

D10

D9

D8

D7

D6

D5

D4

D3

D2

D1

D0

0

0

0

0

0

0

0

0

PCB Temperature

Higher Precision Temperature Readings Registers

These registers provide higher precision readings of the current Zynq and PCB temperatures.

Higher Precision Zynq Core Temperature

Function:

Higher precision measured Zynq Core temperature on Interface Board.

Type:

signed word (16-bits) for integer part and unsigned word (16-bits) for fractional part

Data Range:

0x0000 0000 to 0xFFFF FFFF

Read/Write:

R

Initialized Value:

Measured Zynq Core temperature on Interface Board

Operational Settings:

The upper 16-bits represent the signed integer part of the temperature and the lower 16-bits represent the fractional part of the temperature with the resolution of 1/1000 of degree Celsius. For example, if the register contains the value 0x002B 0271, this represents Zynq Core Temperature = 43.625° Celsius, and value 0xFFF6 0177 represents -10.375° Celsius.

D31

D30

D29

D28

D27

D26

D25

D24

D23

D22

D21

D20

D19

D18

D17

D16

Signed Integer Part of Temperature

D15

D14

D13

D12

D11

D10

D9

D8

D7

D6

D5

D4

D3

D2

D1

D0

Fractional Part of Temperature

Higher Precision Interface PCB Temperature

Function:

Higher precision measured Interface PCB temperature.

Type:

signed word (16-bits) for integer part and unsigned word (16-bits) for fractional part

Data Range:

0x0000 0000 to 0xFFFF FFFF

Read/Write:

R

Initialized Value:

Measured Interface PCB temperature

Operational Settings:

The upper 16-bits represent the signed integer part of the temperature and the lower 16-bits represent the fractional part of the temperature with the resolution of 1/1000 of degree Celsius. For example, if the register contains the value 0x0020 007D, this represents Interface PCB Temperature = 32.125° Celsius, and value 0xFFE8 036B represents -24.875° Celsius.

D31

D30

D29

D28

D27

D26

D25

D24

D23

D22

D21

D20

D19

D18

D17

D16

Signed Integer Part of Temperature

D15

D14

D13

D12

D11

D10

D9

D8

D7

D6

D5

D4

D3

D2

D1

D0

Fractional Part of Temperature

Higher Precision Functional PCB Temperature

Function:

Higher precision measured Functional PCB temperature.

Type:

signed word (16-bits) for integer part and unsigned word (16-bits) for fractional part

Data Range:

0x0000 0000 to 0xFFFF FFFF

Read/Write:

R

Initialized Value:

Measured Functional PCB temperature

Operational Settings:

The upper 16-bits represent the signed integer part of the temperature and the lower 16-bits represent the fractional part of the temperature with the resolution of 1/100 of degree Celsius. For example, if the register contains the value 0x0018 004B, this represents Functional PCB Temperature = 24.75° Celsius, and value 0xFFD9 0019 represents -39.25° Celsius.

D31

D30

D29

D28

D27

D26

D25

D24

D23

D22

D21

D20

D19

D18

D17

D16

Signed Integer Part of Temperature

D15

D14

D13

D12

D11

D10

D9

D8

D7

D6

D5

D4

D3

D2

D1

D0

Fractional Part of Temperature

Module Health Monitoring Registers

The registers in this section provide module temperature measurement information. If the temperature measurements reaches the Lower Critical or Upper Critical conditions, the module will automatically reset itself to prevent damage to the hardware.

Module Sensor Summary Status

Function:

The corresponding sensor bit is set if the sensor has crossed any of its thresholds.

Type:

unsigned binary word (32-bits)

Data Range:

See table below

Read/Write:

R

Initialized Value:

0

Operational Settings:

This register provides a summary for module sensors. When the corresponding sensor bit is set, the Sensor Threshold Status register for that sensor will indicate the threshold condition that triggered the event.

Bit(s)

Sensor

D31:D6

Reserved

D5

Functional Board PCB Temperature

D4

Interface Board PCB Temperature

D3:D0

Reserved

Module Sensor Registers

The registers listed in this section apply to each module sensor listed for the Module Sensor Summary Status register. Each individual sensor register provides a group of registers for monitoring module temperatures readings. From these registers, a user can read the current temperature of the sensor in addition to the minimum and maximum temperature readings since power-up. Upper and lower critical/warning temperature thresholds can be set and monitored from these registers. When a programmed temperature threshold is crossed, the Sensor Threshold Status register will set the corresponding bit for that threshold. The figure below shows the functionality of this group of registers when accessing the Interface Board PCB Temperature sensor as an example.

Module Sensor Registers

Sensor Threshold Status

Function:

Reflects which threshold has been crossed

Type:

unsigned binary word (32-bits)

Data Range:

See table below

Read/Write:

R

Initialized Value:

0

Operational Settings:

The associated bit is set when the sensor reading exceed the corresponding threshold settings.

Bit(s)

Description

D31:D4

Reserved

D3

Exceeded Upper Critical Threshold

D2

Exceeded Upper Warning Threshold

D1

Exceeded Lower Critical Threshold

D0

Exceeded Lower Warning Threshold

Sensor Current Reading

Function:

Reflects current reading of temperature sensor

Type:

Single Precision Floating Point Value (IEEE-754)

Data Range:

Single Precision Floating Point Value (IEEE-754)

Read/Write:

R

Initialized Value:

N/A

Operational Settings:

The register represents current sensor reading as a single precision floating point value. For example, for a temperature sensor, register value 0x41C6 0000 represents temperature = 24.75° Celsius.

Sensor Minimum Reading

Function:

Reflects minimum value of temperature sensor since power up

Type:

Single Precision Floating Point Value (IEEE-754)

Data Range:

Single Precision Floating Point Value (IEEE-754)

Read/Write:

R

Initialized Value:

N/A

Operational Settings:

The register represents minimum sensor value as a single precision floating point value. For example, for a temperature sensor, register value 0x41C6 0000 represents temperature = 24.75° Celsius.

Sensor Maximum Reading

Function:

Reflects maximum value of temperature sensor since power up

Type:

Single Precision Floating Point Value (IEEE-754)

Data Range:

Single Precision Floating Point Value (IEEE-754)

Read/Write:

R

Initialized Value:

N/A

Operational Settings:

The register represents maximum sensor value as a single precision floating point value. For example, for a temperature sensor, register value 0x41C6 0000 represents temperature = 24.75° Celsius.

Sensor Lower Warning Threshold

Function:

Reflects lower warning threshold of temperature sensor

Type:

Single Precision Floating Point Value (IEEE-754)

Data Range:

Single Precision Floating Point Value (IEEE-754)

Read/Write:

R/W

Initialized Value:

Default lower warning threshold (value dependent on specific sensor)

Operational Settings:

The register represents sensor lower warning threshold as a single precision floating point value. For example, for a temperature sensor, register value 0xC220 0000 represents temperature = -40.0° Celsius.

Sensor Lower Critical Threshold

Function:

Reflects lower critical threshold of temperature sensor

Type:

Single Precision Floating Point Value (IEEE-754)

Data Range:

Single Precision Floating Point Value (IEEE-754)

Read/Write:

R/W

Initialized Value:

Default lower critical threshold (value dependent on specific sensor)

Operational Settings:

The register represents sensor lower critical threshold as a single precision floating point value. For example, for a temperature sensor, register value 0xC25C 0000 represents temperature = -55.0° Celsius.

Sensor Upper Warning Threshold

Function:

Reflects upper warning threshold of temperature sensor

Type:

Single Precision Floating Point Value (IEEE-754)

Data Range:

Single Precision Floating Point Value (IEEE-754)

Read/Write:

R/W

Initialized Value:

Default upper warning threshold (value dependent on specific sensor)

Operational Settings:

The register represents sensor upper warning threshold as a single precision floating point value. For example, for a temperature sensor, register value 0x42AA 0000 represents temperature = 85.0° Celsius.

Sensor Upper Critical Threshold

Function:

Reflects upper critical threshold of temperature sensor

Type:

Single Precision Floating Point Value (IEEE-754)

Data Range:

Single Precision Floating Point Value (IEEE-754)

Read/Write:

R/W

Initialized Value:

Default upper critical threshold (value dependent on specific sensor)

Operational Settings:

The register represents sensor upper critical threshold as a single precision floating point value. For example, for a temperature sensor, register value 0x42FA 0000 represents temperature = 125.0° Celsius.

FUNCTION REGISTER MAP

KEY

Configuration/Control

Measurement/Status/Board Information

MODULE INFORMATION REGISTERS

OFFSET

REGISTER NAME

ACCESS

OFFSET

REGISTER NAME

ACCESS

0x003C

FPGA Revision

R

0x0074

Bare Metal Revision

R

0x0030

FPGA Compile Timestamp

R

0x0080

Bare Metal Compile Time (Bit 0-31)

R

0x0034

FPGA SerDes Revision

R

0x0084

Bare Metal Compile Time (Bit 32-63)

R

0x0038

FPGA Template Revision

R

0x0088

Bare Metal Compile Time (Bit 64-95)

R

0x0040

FPGA Zynq Block Revision

R

0x008C

Bare Metal Compile Time (Bit 96-127)

R

0x0090

Bare Metal Compile Time (Bit 128-159)

R

0x0094

Bare Metal Compile Time (Bit 160-191)

R

0x007C

FSBL Revision

R

0x00B0

FSBL Compile Time (Bit 0-31)

R

0x00B4

FSBL Compile Time (Bit 32-63)

R

0x00B8

FSBL Compile Time (Bit 64-95)

R

0x00BC

FSBL Compile Time (Bit 96-127)

R

0x00C0

FSBL Compile Time (Bit 128-159)

R

0x00C4

FSBL Compile Time (Bit 160-191)

R

0x0000

Interface Board Serial Number (Bit 0-31)

R

0x0010

Functional Board Serial Number (Bit 0-31)

R

0x0034

Interface Board Serial Number (Bit 32-63)

R

0x0014

Functional Board Serial Number (Bit 32-63)

R

0x0008

Interface Board Serial Number (Bit 64-95)

R

0x0018

Functional Board Serial Number (Bit 64-95)

R

0x000C

Interface Board Serial Number (Bit 96-127)

R

0x001C

Functional Board Serial Number (Bit 96-127)

R

0x0070

Module Capability

R

0x01FC

Module Memory Map Revision

R

MODULE MEASUREMENTS REGISTERS

OFFSET

REGISTER NAME

ACCESS

OFFSET

REGISTER NAME

ACCESS

0x0200

Interface Board PCB/Zynq Current Temp

R

0x0208

Functional Board PCB Current Temp

R

0x0218

Interface Board PCB/Zynq Max Temp

R

0x0228

Functional Board PCB Max Temp

R

0x0220

Interface Board PCB/Zynq Min Temp

R

0x0230

Functional Board PCB Min Temp

R

0x02C0

Higher Precision Zynq Core Temperature

R

0x02C4

Higher Precision Interface PCB Temperature

R

0x02E0

Higher Precision Functional PCB Temperature

R

MODULE HEALTH MONITORING REGISTERS

OFFSET

REGISTER NAME

ACCESS

OFFSET

REGISTER NAME

ACCESS

0x07F8

Module Sensor Summary Status

R

Module Sensor Registers Memory Map

REVISION HISTORY

Motherboard Manual - Module Common Registers Revision History

Revision

Revision Date

Description

C

2023-08-11

ECO C10649, initial release of module common registers manual.

C1

2024-05-15

ECO C11522, removed Zynq Core/Aux/DDR Voltage register descriptions from Module Measurement Registers. Pg.16, updated Module Sensor Summary Status register to add PS references; updated Bit Table to change voltage/current bits to 'reserved'. Pg.16, updated Module/Power Supply Sensor Registers description to better describe register functionality and to add figure. Pg.17, added 'Exceeded' to threshold bit descriptions. Pg.17-18, removed voltage/current references from sensor descriptions. Pg.20, removed Zynq Core/Aux/DDR Voltage register offsets from Module Measurement Registers. Pg.20, updated Module Health Monitoring Registers offset tables.

C2

2024-07-10

ECO C11701, pg.16, updated Module Sensor Summary Status register to remove PS references;updated Bit Table to change PS temperature bits to 'reserved'. Pg.16, updated Module SensorRegisters description to remove PS references. Pg.20, updated Module Health MonitoringRegisters offset tables to remove PS temperature register offsets.

DOCS.NAII REVISIONS

Revision Date

Description

2025-11-05

Corrected register offsets for Interface Board Min Temp and Function Board Min & Max Temps.

2026-03-02

Formatting updates to document; no technical changes.

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