A2000 Autoconfig Help - GottaGoFastRAM

[psoma]

Thanks for the other things to try - Buster is the only thing I haven't done there now... unfortunately I don't have access to a MOS one (current one is CSG), but I did notice if I disable the 8MB GottaGoFast RAM, this thing is stable. I'm thinking it's some kind of DMA issue to the FastRAM. Performance isn't a big issue, it goes from 1.8MBps to 1.5MBps which I can handle... so can I permanently force DMA to ChipMem instead?

I've tried changing the Mask to 0xfffff, but that doesn't seem to work. Any other tricks to force DMA to Chip?

[LIV2]

Strange that there are any issues with DMA, the board was tested extensively with my A500+A590 and A2091 in the 2000.

Amiga.resource mentions some kind of "U605 patch" has this been applied?

Not sure about DMA mask etc unfortunately

[Thomas Richter]

Note that you have only 8MB of autoconfig space, plus a little bit of IO space. Thus, if the RAM under the CPU takes 8MB, there is no (large) autoconfig block left. There are then only 64K I/O blocks left which may or may not be sufficient.

Also check whether a board-upgrade has been applied. This implies moving a resistor pack o the bus drivers driving the Zorro slots. No matter the board upgrade, my experience with Rev.4 boards are relatively "mixed" in the sense that I never got them working stable. The rev.6 work better.

[psoma]

Originally Posted by LIV2

Strange that there are any issues with DMA, the board was tested extensively with my A500+A590 and A2091 in the 2000.

Amiga.resource mentions some kind of "U605 patch" has this been applied?

Not sure about DMA mask etc unfortunately

Yeah, have applied the U605 patch (pullup resistor between pins 11 and 20) - I don't think it's a DMA issue with the GottaGoFast so much, reading a few other posts, people have had issues with the HardFrame on early revision 2000s, so I think it's just unfortunate that this particular SCSI card (which is apparently the fastest Zorro II option) doesn't like 4.0 as per @Thomas Richter's comment.

With regard to the upgrades, I followed the guide at https://pastebin.com/CR7WBXxW and have completed those mods, though none were around a resistor pack relocation... happy to try it if you have any more details?!?

Thanks!