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XO: Pulse Output Pin (Audio)

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 will pulse any of the control pins on the FAST Audio Interface Board.

Where <OUTPUT> is a number 0 - 7 * 0 = LCD Control Pin 1 * 1 = LCD Control Pin 2 * 2 = LCD Control Pin 3 * 3 = LCD Control Pin 4 * 4 = LCD Control Pin 5 * 5 = LCD Control Pin 6 * 6 = PC Control Power Pin * 7 = PC Control Reset Pin

And where <Data> is a 32-bit value representing the time in milliseconds to pulse the pin low for.

Example set LCD Pin 2 low for 50ms (0x32 in hex)

XO:1, 32<CR>

Returns XO:P<CR>

Multiple outputs can be set low at the same time, but sending a new XO command to the same pin will set the cancel the previous time and set the new time.

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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