Dreamcast controller sub pcb

So, I stuffed a va1 main board inside a va0 unit in the hopes of getting a working Dreamcast. Nothing. There's a short between 5v and gnd. Removing the 20 pin ribbon makes the system boot so I turn my attention to the controller port board. I suspect that it actually has a different pinout to later revisions but it's hard to find clear info. Can anyone confirm?

If so, I can get my hands on a pcb marked KATANA SUB BD 2 839-1124. Is this va1 compatible?

Thanks!

 

Va0 and va1 controller pcbs are not interchangeable

 

No, the VA0 and VA1 controller PCBs are not interchangeable. The 839-1124 board is the correct one for a VA1, but you will also need to replace the fan, since the VA0 unit has a 2 pin fan with no tachometer output and the VA1 will shut down if it doesn't see the tachometer signal.

 

Thanks for confirming! I guess there is no easy way to bypass the tachometer check?

 

With an arduino its simple =) There is a thread on it here somewhere.

Edit: Here http://assemblergames.com/l/threads/dreamcast-fan-mod-with-an-arduino.57434

 

Thanks, but I was thinking more along the lines of cutting a trace or something. Since it boots if you unplug the control port board it seems like you would be able to just block the signal from reaching the main board.