Disabling SCSI parity checking to dump disk on ACB4000 MFM-SCSI adapter?

[Plamen Mihaylov]

I have the same problem with Torch Triple X disk which uses OMT SCSI/MFM
adapter.
I believe the best solution is to use David’s MFM emulator board.

Best regards,
Plamen

On Wednesday, September 23, 2020, Michael Engel via cctech <
cctech at classiccmp.org> wrote:

>
>
> On 9/23/20 8:54 PM, Grant Taylor via cctech wrote:
>
>> On 9/23/20 12:51 PM, Michael Engel via cctech wrote:
>>
>>> Do you know if is there another OS which would make it easier to change
>>> crucial SCSI parameters in the driver (config) or maybe a specialized tool
>>> that could help me to image the disk?
>>>
>>
>> Try booting off of a Linux live CD / DVD and seeing if it will behave any
>> different
>>
> Not really, unfortunately. The error messages are a bit cryptic:
>
> [ 1069.277571] (scsi8:A:0:0): Sending SDTR period 45, offset 0
> [ 1069.278961] scsi 8:0:0:0: Attempting to queue a TARGET RESET message
> [ 1069.278964] CDB: 0x12 0x0 0x0 0x0 0x24 0x0
> [ 1069.278975] scsi 8:0:0:0: Command not found
> [ 1069.278979] aic7xxx_dev_reset returns 0x2002
> [ 1069.279286] (scsi8:A:0:0): Sending SDTR period 45, offset 0
> [ 1069.280736] scsi8: Slave Alloc 1
> [ 1069.543400] scsi target8:0:1: asynchronous
> [ 1069.543416] scsi8: target 1 using asynchronous transfers
> [ 1069.543420] scsi8: Selection Timeout on A:1. 0 SCBs aborted
>
> It seems that the problem lies in the firmware of the ACB4000, which
> doesn´t seem to support some standard commands, e.g. the INQUIRY command.
> Most recent Linux SCSI drivers seem to use this command.
>
> Some information on this problem can be found here:
> https://www.zot.org/~hamish/hacks/acb-4000.html
>
> There´s a thread (in German, sorry) in which someone tried to get a disk
> on an ACB4000 to work:
> https://de.comp.os.unix.linux.misc.narkive.com/ti21cHO0/scsi
> -1-platte-unter-linux-ansprechen
> and somebody else (also in German...) claims that he could run a disk on
> an ACB4000 (from an Atari SH204) on an Adaptec 1542:
> https://forum.classic-computing.de/forum/index.php?thread/
> 18576-wie-programme-vom-pc-auf-atari-mega-st-bringen/&pageNo=2
>
> So maybe an Atari ST with an ACSI->SCSI adapter might help. That seems to
> be one of the machines we don´t have here...
>
> -- Michael
>
>