exxos's Atari, Amiga & retro forum

Hello Exxos, i have Exxos muti TOS chip 1.04/2.06 on my STF.

Do you think is it possible to have special version of a chip with a patch to invert floppy drive internal to B: and external to A: and so booting for external ?

I hope you can. Thanks in advance.

Normally people do this by swapping the drive select signals from the YM chip IIRC.

exxos wrote: 30 Jun 2024 18:16 Normally people do this by swapping the drive select signals from the YM chip IIRC.

I read that but it's better for me to not cut the motherboard if it's possible to do that in TOS.

You will te me if you can do that.

gigi92 wrote: 30 Jun 2024 19:36 I read that but it's better for me to not cut the motherboard if it's possible to do that in TOS.

You will te me if you can do that.

Me patch TOS ? I am the wrong person to ask that. While I patched TOS for ST536 it took a very long time to figure out, and that was with the routines I needed already within TOS. I would have to charge for all my time involved to do such things, which would likely run up to 4 figures. But I don't think it's a good idea, as it would likely only work for clean GEM apps anyway.

i understant , thanks for thinking.

i also read on stf : W2 on board for change external drive to DS1 (pin 2-3) to DS0 (pin 1-2) signal to pin 5.
And change on internal floppy drive jumper for DS0 (default) to DS1.

do you know this "W2" ?

@gigi92

I think what you're asking is impractical and out of the scope of what's possible through this forum or the store.

Essentially you're asking for two versions of TOS that allow you to select which drive to boot from on demand.

It's a lot of work for anyone to undertake, especially for one request.

If you aren't prepared or able to do the hardware mod, I'd suggest that you have a look over at 8bitchip.info as PPera does have some custom versions of TOS and may be able to help.


BTW I did this specific mod here: https://www.exxosforum.co.uk/forum/vie ... start=190

AFAIK, some games may also implement their own low level disk access, avoiding the TOS calls. So doing it in software wouldn't work 100% of the time anyway