exxos's Atari, Amiga & retro forum

LIV2 wrote: 09 Mar 2021 17:46 Yep, you're meant to do some bus arbitration before asserting boss (/BR, wait for /BG then assert /BOSS) before Buster will give the copro control but if you haven't got a CPU in the motherboard socket you can just ground /BOSS on the riser and you're good to go.

I am working on adding proper arbitration to SukkoPeras riser (so you can leave the other cpu in) as I need to test that the copro arbitration of my Buster replacement but I'm not sure when I'll have that done

As a step to that I've already updated his adapter to add solder jumpers to ground /BOSS and cut off the E clock which has been upstreamed to his repo

LIV2 wrote: 09 Mar 2021 17:12 I see several mentions that the 536 locks up when using with the A2091 and thought I'd post my findings in regard to that

While working on the Buster CPLD replacement I found that Buster doesn't signal bus requests to the coprocessor slot unless /BOSS is asserted which causes the A2091 to lock up as it never gets a bus grant (because the CPU never sees the request).

I found that grounding the /BOSS signal on my coprocessor slot adapter and that allowed the system to boot so if your system needs to support DMA of some kind (Like if you use the A2091 with vb2091 to support DMA in a Z3 system) you will want to do this unless the TF is plugged into the CPU socket rather than the slot.

patracy wrote: 29 Mar 2021 19:11 Just curious, I'm going to be building a 2000 box in the future that will ultimately end up with a Buffee CPU, zz9000 video card, and a buddha IDE controller. In the mean time I was thinking about a TF536 until the buffee comes in. But can the IDE on the TF536 be disabled? Mainly thinking of it as a temporary accelerator that I might use in a future machine (A500 maybe?) at a later date if it can play with a Buddha.

patracy wrote: 29 Mar 2021 19:21 I had planned on using the buddha IDE controller for the HD controller. I guess I could not use the buddha at all until I get the buffee.

patracy wrote: 29 Mar 2021 19:21 I had planned on using the buddha IDE controller for the HD controller. I guess I could not use the buddha at all until I get the buffee.