Amiga 2000 with SCSI and IDE

[decnet]

Hi, I don't know if anyone can help but I've been playing around with the setup I have for a few days now and can't get any further so thought I'd ask here.

I have an Amiga 2000 with the A2091 SCSI controller (version 7 ROMs), which until recently I was using with a 4GB SCSI drive and a SCSI CD drive without issue. I decided to add a Buddha Flash (Phoenix Edition) card to the machine combined with a TrueIDE adapter and two flash cards with the aim of removing the SCSI hard drive while retaining the CD drive. The Buddha, TrueIDE and flash cards all worked well, I installed AmigaOS 3.9 onto the first flash card and as it was set to be the bootable partition everything worked as expected.

My problem started when I wanted to stop using the SCSI hard drive. I unplugged the power to the drive but now the machine didn't boot, however if you put a CD (any CD) into the CD drive it did boot which led me to assume it's trying to auto boot from the CD drive only and if it doesn't find one won't try the flash drive for some reason. I changed the auto boot jumper on the A2091 to disable auto booting but when I do this although the machine boots it doesn't recognise the CD drive at all and there's an error at startup.

Does anyone have any ideas, I'm happy to try any suggestions or provide more information.

Thanks.

[gertsy]

Weird, so the SCSI CDROM wont function without the Auto Boot jumper short. But Buddha boots the flash fine.
Could it be a SCSI termination issue for the CDROM?  Perhaps the SCSI HD drive being powered off is screwing the termination or something?

[decnet]

Thanks for the reply, the CD drive doesn't function with the auto boot jumper set to disabled nope, it has active termination set to on and has a device ID of 4, which from what I've read should be ok as it's always been the last device on the chain. Like you say it must related to the hard drive being unplugged but I'm not sure what's going on with it.

[danbeaver]

What is the boot priority of the CF drive?  When you say "unplugged" the SCSI drive did you mean it is no longer connected to the SCSI cable or no longer powered?   When you right click to get to the startup menu on booting, can you select the CF card?  If so, I would leave the autoboot on and work on the boot priority.

[decnet]

Hi, I'll try and answer as best I can, the first flash drive (actually the first partition on it) has a boot priority of zero and is the only partition that is set to be bootable (this is what's reported in HDTools if that's the right / only place to be checking). Yes I unplugged the power and then later unplugged the SCSI cable from the hard drive to see if it would make any difference but it didn't.

I can see the flash cards in the startup menu and after DF0 the next device listed is the bootable partition on the first flash card, so I guess that looks ok. I think you're right about keeping the auto boot enabled on the SCSI card, is there anything else I can check or change relating to the boot order to stop it trying the CD drive maybe.

Thanks.

[danbeaver]

Yes, try a boot priority that is higher to force the OS to bypass the CD; I'm not used to the setup with two controllers, but if it boots without the A2091 to the CF card, then you should bypass the SCSI CDROM at a priority of 11 ( OS4.1 has the CD set at 10 I believe).

[decnet]

Thanks for the suggestion, I've changed the boot priority from 0 to 11 but the same problem persists unfortunately. I've also tried putting the Buddha in the zorro slot next to the accelerator card and the A2091 at the opposite end in case there's a priority dictated by where the card is located but that doesn't seem to have made any difference either.

[Ral-Clan]

I've seen Amiga systems before where I had to leave a non-bootable CD in the CD drive in order to the get the bootstrap to bypass the drive and move on to the next bootable drive.

I don't know much about IDE, but can you set the Rigid Disk Block setting on the CF card to increase its priority (this might be what someone else suggested)?

[Matt_H]

I'm guessing there's a termination issue. But if you can't resolve that, disabling autoboot seems to be the way to go. The thing you were missing is that you need a software version of the ROM in SYS:Expansion. Without that, the card is essentially disabled when autoboot is off.

V6.x of the soft-ROM is on the 2091 install disk available from various sources. Someone here (SpeedGeek, maybe?) recently put together a v7.0 soft-ROM, which Commodore never did. Search the forums and you should find it.

[decnet]

That sounds promising, I'll have a look for the right soft-rom and give it a go.

Thanks.

[danbeaver]

I believe the Soft ROM is just a software extension the speed up the card especially when the card is modified  with the 14 MHz jumper.  Card position won't change anything but automatic memory config order.  Did you think of just using an IDE CDROM?  They are considerably less expensive than the SCSI ones

[decnet]

I've already got a SCSI CD drive but I think you're right about not using this SCSI controller, I've tried everything I can and it won't play ball so I've removed it, which is useful in some ways as it frees up a Zorro slot. If I get another accelerator in the future with a SCSI controller then I'll be able to use the CD drive again.

Thanks for the help everyone.

[Ral-Clan]

I don't know if anyone has mentioned this before, but the A2091 was never great with removable media devices. When I had one I used the GuruROM with it and it worked fine, but the Commodore ROMs (even 7.0) were probably designed a few years before CD drives became commonplace in computers.

[gertsy]

I've already got a SCSI CD drive but I think you're right about not using this SCSI controller, I've tried everything I can and it won't play ball so I've removed it, which is useful in some ways as it frees up a Zorro slot. If I get another accelerator in the future with a SCSI controller then I'll be able to use the CD drive again.

Thanks for the help everyone.

You can always used an IDE CDROM/DVD with your Buddha as slave.

[Matt_H]

I believe the Soft ROM is just a software extension the speed up the card especially when the card is modified  with the 14 MHz jumper.

No, that's something separate. All hardware needs a corresponding software driver. Most disk controllers have this in ROM onboard. Other devices use disk-based drivers (in SYS:Expansion, Devs: or Libs: for instance). With the onboard ROM disabled, the 2091 needs a disk-based driver.

I think, though, that there is an optimized version of the soft ROM for boards that have the 14MHz mod. There may be a related software patch as well for cases where the onboard ROM isn't disabled. Maybe you're thinking of one of those.