Troubleshoot VIPER

Stop configuration changes when communication or measurements are unreliable.

Mock data does not represent connected hardware.

Common problems

Problem	Check or action
Cannot open VIPER	Confirm Pi power and Ethernet. Try the IP address shown on the touchscreen.
Static address does not respond	Match the computer’s subnet. Check for duplicate addresses. See Network setup.
Interface opens; hardware service is unreachable	Restart VIPER using the command below.
No power supply appears	Check input power, the Aardvark connection, and the supplied I2C wiring.
Power-supply data shows mock mode	Restart VIPER. Confirm actual hardware detection before continuing.
Scope shows mock mode	Connect the DC adapter. Reconnect USB and restart VIPER.
I2C reports “wrote 0 of N bytes”	Check power, cabling, and pull-up settings. Ask NAI Support before changing bus settings.
Beagle is missing	Reconnect its USB cable and restart VIPER.
Configuration writes fail	Check communication and S3 NVMRO. The revision 3 backplane permits writes with S3 down.
Outputs remain off	Check input power, enable/inhibit controls, hardware switches, and displayed faults.
A rail shows a fault	Check the reported condition, load, and cooling before retrying.

See Hardware setup for connections and switch positions.

Restart VIPER

Prepare the connected load before restarting software. Restarting the interface does not guarantee disabled outputs or released manual reset.

Run this command in a Pi terminal:

bash ~/viper-backend/restart-viper.sh

Decline the optional code update unless NAI Support directs otherwise.

For the SRC build, release manual SYSRESET before ending the test.

Scope display problems

Problem	Action
Time-window label disagrees with the axis	Adjust Pts, then check the axis again.
Waveform appears choppy	Try 2 k display points and a 5 ms block length.
Voltage appears to halve across the chart	Measure the signal separately. Report the display issue to NAI Support.

Do not change power-supply settings to compensate for an unverified display error.

Startup diagnostics

With terminal access, check the local services:

curl http://localhost:3001/api/status
curl http://localhost:5173

Read recent service logs:

tail -n 100 /tmp/viper-backend.log /tmp/viper-frontend.log

For missing modules, dependencies, or startup files, contact NAI Support rather than rebuilding the installed software.

Request support

Provide the model, dashcode, serial number, firmware revision, exact error, and steps that reproduce it. Include relevant screenshots or logs. Do not include passwords or credentials.