I'm getting "No IO, retry x"

Make sure your JVS cable is plugged into the connector marked 'JVS'.  JVS uses the same connector as USB, which is a major source of confusion, especially on boards like the Jammafier that has both USB and JVS.

I'm getting "Unknown IO"

This is because you are (one of) the first to use the Jammafier with that particular IO board.  Please get in touch so the firmware can be updated and correctly identify it.  

What is the USB port used for?

The USB port can be used to power 5V devices from the cabinet power supply.

Can the Jammafier be used in LCD cabinets like the Taito Vewlix?

Yes - but video will have to go through a scaler.

I want to use a video processor/up-scaler, but it only has connector X for input, what do I do?

Sorry about connector X, it can be a real PITA.  Your best bet is to find a plain connector X to VGA cable, or make your own.

If you make your own, you can find nice breakout's on ebay by searching for "VGA MALE BREAKOUT SHELL".

I need a cheap scaler/ Can I use the Jammafier with the GBS-8200?

The GBS-8200 is a cheap scaler readily available on ebay.  The picture quality is not stellar by any means, and the picture has some noise and color issues - but should serve your scaling needs in a pinch.  Simply use a normal VGA cable between the Jammafier and the GBS-8200.  You need to tweak the pots on the GBS-8200 a bit to scale down the video signal.  To avoid a bit of messy cabling, the GBS-8200 can be powered from the Jammafier using the USB port, search ebay for 'USB BARREL JACK', and you should find a suitable power cable cable.

Why is it called Jammafier?

For lack of a better name - it was originally named JVS2JAMMA, but some people confused this with an IO board for Jamma cabinets.