Minimig ITX / TF536 and attempting to use scsi.device on both

[Dr. Gonzo]

So finally finished building a couple Minimig ITX 1.97 boards and am building one up with a TF536 I threw together as well some time back.  Everything seems to be cooperating with them, but I'd like to have .hdf file(s) on the SD card in the Minimig and put a physical CD-ROM and ZIP drive on the IDE port on the TF536.  However, when I have the TF536 installed, I no longer seem to be able to access the .hdf files on the Minimig SD card.  I can see a physical or SD card reader on the TF536 in HD Toolbox and everything works fine.  If I pull it out and just use a 68000 on the Minimig, the .hdf files work fine.  Both controllers use scsi.device so wondering if the TF536 controller stomps over the Minimig's and somehow disables it?  I can't find any other instances of this coming up in my searches, but do see people with multiple physical cards on a 2000 (for instance) that all use scsi.device having to jump through some hoops to get them working together, with some saying you have to disable autoboot to get them to work together.  I don't believe I have that option on either the Minimig or TF536.  Both are on the latest firmware I could find with the Minimig using the TF53x core.

Sorry for the long winded question, but anyone have any experience with trying to do this and/or have any advice to get this going?  Hopefully I put this in the right forum as it's 'sort of' emulation. 

Thanks in advance!
~Dr. G

[Thomas]

There is a big difference between multiple IDE expansions in an A2000 and the mainboard IDE of an A600 or A1200.

The former do Autoconfig which lets the OS assign a different memory address to each expansion. The latter just appears at a fixed memory address.

And that's your problem: both the Minimig and the TF mimic the onboard IDE at its fixed memory address. As the CPU is on the TF, it takes precedence and overlays the same address of the Minimig. You cannot use both at the same time.

[Dr. Gonzo]

Ah, Thank You for the explanation, makes sense.  I assume it's not something as simple as selecting a different memory region in the source and building new a new .jed for the TF?  Probably beyond my abilities anyway, but I'm grasping at straws as I'd really like to use the 44 pin IDE for the CD and ZIP drives.

Thx again!
~Dr. G

[Thomas]

I am not a hardware expert but I believe in theory this should be possible. You would also have to make a 2nd.scsi.device which looks at the new address range. And you won't be able to boot from the TF IDE any more unless you hack a Kickstart ROM which contains both scsi.device drivers.

[F0LLETT]

I am not a hardware expert but I believe in theory this should be possible. You would also have to make a 2nd.scsi.device which looks at the new address range. And you won't be able to boot from the TF IDE any more unless you hack a Kickstart ROM which contains both scsi.device drivers.

Could you use the 2nd.scsi.device from A4000T rom?

[Thomas]

No. The name "scsi.device" does say nothing about its function. The A4000T ROM has a scsi.device for IDE and another one for SCSI. There are many more expansions which use the name scsi.device for their drivers, but they are all for different hardwares. It is a convention that drivers which find the name scsi.device already in use rename themselves to 2nd.scsi.device, 3rd.scsi.device and so on. The same happens in the A4000T. If there are no IDE devices, the SCSI driver is called scsi.device. If there are no SCSI devices, the IDE driver is scsi.device. If both are present, IDE is scsi.device and SCSI is 2nd.scsi.device.

[F0LLETT]

No. The name "scsi.device" does say nothing about its function. The A4000T ROM has a scsi.device for IDE and another one for SCSI. There are many more expansions which use the name scsi.device for their drivers, but they are all for different hardwares. It is a convention that drivers which find the name scsi.device already in use rename themselves to 2nd.scsi.device, 3rd.scsi.device and so on. The same happens in the A4000T. If there are no IDE devices, the SCSI driver is called scsi.device. If there are no SCSI devices, the IDE driver is scsi.device. If both are present, IDE is scsi.device and SCSI is 2nd.scsi.device.

So just renaming would not work, as you would still need the driver to point to another address, else it would still conflict I'm guessing.