exxos's Atari, Amiga & retro forum

I watched this thread with interest a while back , but was under the impression that it was a bit more complex to properly hold the on-board 68000 in reset and would require bus arbitration code to be added to the accelerator firmware.

I appreciate that it works in a different way but I think this is the relevant code from the Vampire 600 sources ( I think themselves adapted from the Minimig source ) :

https://github.com/robinsonb5/Vampire60 ... et_fsm.vhd

dalek wrote: 26 Nov 2019 06:48 Just FYI in case you haven't seen it, over at a1k.org Matze has a design for a 68000-DIP->68000-DIP switch for the A500 that I've been meaning to try out one day...

I think that is solving a slightly different problem. In that design he has control over signal selection on both CPUs via a multiplexer before they get to the motherboard. The A600 CPU can't be bypassed in that way unfortunately.

E and vma, vpa being an input. In A600 it's connected to bus request to use the same 1k pull-up. Pulling BR low would also pull VPA low, but probably that (VPA) doesn't interfere with bus request.

I posted a couple of ideas in how to get the TF536 to fit using one of these style adaptors on a thread in the TF536 forum

As I would love one of these in my A600, any comments, ideas of input would be great

https://www.exxosforum.co.uk/forum/viewt ... =10#p44272