exxos's Atari, Amiga & retro forum

exxos wrote: 23 Nov 2022 21:19 Have you guys experimented with the load modules into TT RAm option ?

exxos wrote: 23 Nov 2022 21:19 Have you guys experimented with the load modules into TT RAm option ?

markus0321 wrote: 23 Nov 2022 19:42 I haven't been able to do all the tests since yesterday. But what I was able to check when I have EmuTOS running tells me that the problem with SCSI and FDD does not occur with EmuTOS.
I even eliminated this strange clockpatch (47ohm) and it still works fine for me with SCSI under EmuTOS. I also tried to program TOS4.04 to the flach memory on the DFB1 board because I thought maybe I had a faulty eprom on the board but it didn't change anything and using TOS4.04 the problems with SCSI come back.

dml wrote: 24 Nov 2022 08:10 TOS 4.0x ignores the _FRB cookie. It is a non-system cookie, only observed by disk driver software interested to look for one and use it.

@Rustynutt I had a quick look at the AB driver software last night and it is installing a 64k _FRB. Which ties with the docs:

Code: Select all

3.7.2.579 Cookie, _FRB

Fast-RAM buffer

The cookie points to a 64 kbyte size buffer in ST-RAM that can be used by an Atari TT for ACSI-DMA transfers (the Fast-RAM of the TT can not be used for this).

Device drivers for the ACSI port may use this buffer as temporary storage for transfers into the Fast-RAM; access is coordinated via the system variable flock.

If this cookie is not present, then the computer either has no Fast-RAM, or no ACSI port.

Badwolf wrote: 23 Nov 2022 22:42

markus0321 wrote: 23 Nov 2022 19:42 I haven't been able to do all the tests since yesterday. But what I was able to check when I have EmuTOS running tells me that the problem with SCSI and FDD does not occur with EmuTOS.
I even eliminated this strange clockpatch (47ohm) and it still works fine for me with SCSI under EmuTOS. I also tried to program TOS4.04 to the flach memory on the DFB1 board because I thought maybe I had a faulty eprom on the board but it didn't change anything and using TOS4.04 the problems with SCSI come back.

Thank you for testing this thoroughly. So if you're sure that SCSI works with TT-RAM and acceleration under EmuTOS then I think we can tentatively rule out a hardware problem and then focus just falls on the software. Primarly HDDriver or FASTRAM/MAPROM, but perhaps even TOS4.

Now I know Anders wrote an updated MAPROM/FASTRAM (they're the same program, but FASTRAM skips the remapping of ROM with MMU) but it doesn't seem to work properly with DFB1. I did take a look haven't had time to do so properly. It's possible there's a bug in the old 2.2 version regarding the FRB. Unfortunately Anders isn't around at the moment to ask.

It's also possible TOS4.04 simply ignores the FRB because it's not expected to be needed. I had, to be honest, read that it only affected transfers from/to ACSI ports.

It's also possible it's an HDDriver bug.

Depending on the format of your partition table, it may be possible to floppy-load Atari's old AHDI and repeat the read/write tests.

Anyway, if we can figure out the correctly working combination I can update the FAQs.

Thank you again for bringing this up as it's not something I would have found myself & thanks everyone else for their input so far. :cheers:

BW

Rustynutt wrote: 24 Nov 2022 08:57 Guess at this point, a discussion here on the below link could be moved. This sounds very AB specific. I'm not picky that way, but offering courtesy :)
https://www.hddriver.net/forum/viewtopic.php?t=286