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QP: Lamp Test Mode (Retro Platform)

FAST Serial Protocol: Overview & First Steps

This documentation section is about the FAST Serial Protocol (FSP) commands, which are the low-level commands a host computer sends to a FAST board. Most FAST Pinball makers do not need to know about these details, since the pinball game framework (such as the Mission Pinball Framework) handles this communication for you.

If you're writing your own game framework, we have a series of programming guides. Also, be sure to read the overview of how FSP works and how to connect first.

This command is very similar to the driver test QL: command. To use this command, you do NOT type Enter after the colon. Just type QL: and then use the Q, W, or Space to control the tests. Hit Enter to exit the test mode.

This is an interactive command designed to be used via a terminal emulator.

Note that this is for matrix-style lamps used on the FAST Retro Platform. Modern RGB LEDs can be tested via LED commands.


<TEST_COMMAND> Q = Decrease Lamp Number W = Increase Lamp Number Space = switch between Row/COL or single Lamp

You must enable the watchdog for this to work!

If you're trying this command and nothing seems to be happening, it's probably because the watchdog on the controller has timed out. (For safety reasons, controller will not allow drivers to function until a watchdog command is sent.)

Details are in the watchdog reference section. In the meantime, you can use a value like:


That will enable the drivers for about 90 minutes. Just send a WD:1 when you're done which will disable them (technically that sets the watchdog to 1ms.)

Documentation Feedback? Requests? Confused?

Hi! I'm Brian, and I'm responsible for the documentation at FAST Pinball. If you have any feedback, requests, corrections, ideas, or any other thoughts about the docs, please let me know!

You can email me at I maintain this site in my spare time, so there might be a week or so delay if you email me.

If you have a more pressing need, reach out to us via Slack, or email Aaron Davis.


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