1> http://ibm-pc.org/firmware/other/adaptec/adaptec.htm
2> yes. you might have to enable it in the adaptec bios. I remember mine had the ctrl-A option.
3> maybe the 3.20 firmware will help

luckybob wrote:

1> http://ibm-pc.org/firmware/other/adaptec/adaptec.htm
2> yes. you might have to enable it in the adaptec bios. I remember mine had the ctrl-A option.
3> maybe the 3.20 firmware will help

Thank you!

I read most of your previous posts on this topic, they were very helpful.

Ctrl-A only works when you have devices attached to the SCSI bus. If you only have the card with no devices, it does nothing.

I'm not sure if the 1542B and 1542CF use the same BIOS. If you want I can make an image of my 1542CF BIOS.

stamasd wrote:

Ctrl-A only works when you have devices attached to the SCSI bus. If you only have the card with no devices, it does nothing.

I'm not sure if the 1542B and 1542CF use the same BIOS. If you want I can make an image of my 1542CF BIOS.

I have one hard drive connected. It's fully working, but no CTRL+A message appears. It does detect the drive on ID 0 though.

I've just backed up my 3.1 chips. I'm attaching them to this message in case someone googles and stumbles across here.

I'll leave the current chips intact and order replacements. I don't like pealing off the stickers on the originals 😀

I think you need to enable the BIOS before you can boot from a drive. The drive needs to be set to ID 0.

Unfortunately I can't help you any further because I only own an Adaptec 1520B SCSI-2 adapter, which uses a dipswitch block to enable or disable PnP configuration and the BIOS instead of jumpers...

yawetaG wrote:

I think you need to enable the BIOS before you can boot from a drive. The drive needs to be set to ID 0.

The drive is set to ID 0. AFAIK only ID 0 and ID 1 work. I'm sure the BIOS is enabled, I checked all the jumpers per manual.

Anyway, I'll pick up the project once the replacement chips arrive 😀

PhilsComputerLab wrote:

yawetaG wrote:

I think you need to enable the BIOS before you can boot from a drive. The drive needs to be set to ID 0.

The drive is set to ID 0. AFAIK only ID 0 and ID 1 work. I'm sure the BIOS is enabled, I checked all the jumpers per manual.

Anyway, I'll pick up the project once the replacement chips arrive 😀

Maybe you should then double-check the jumpers, because the 1520B manual explicitly states the Ctrl-A message will only show up if the BIOS is enabled (IIRC, it shows up after POST). I also just read in the 1520B installation guide that booting from a SCSI hard disk will only work if there are no non-SCSI boot devices in the system. Try disabling your IDE channels and see if it works.

The only other reasons listed in that manual for the BIOS Ctrl-A message not showing up are related to resource conflicts and improperly terminated devices or faulty cables, but apparently that should also cause system hangs or instability...

Will do. There is no other IDE controller in the machine, just the 1542B.

Yup it's enabled. If I disable it there is no message. Enabled it states the BIOS version and detects the hard drive and all of that.

I have a 1542B that I was just messing with. I didn't have any issues with it detecting and booting. worked pretty much just as if i was setting an IDE drive up. It was only a 1GB drive though.

heres how mine is jumpered. The floppy controller on the card is disabled. I also originally had issues with a resource conflict with the sound card which I think i remember solving by changing addresses.

Did you try hitting CTRL-A repeatedly throughout the POST process? Maybe the message is going by too fast to see it.

Have you enabled shadow memory in the computers BIOS? It will need that in order to boot.
Does the harddrive have the lowest SCSI Device ID? (can't remember if that is 0 or 1)
Have you terminated the end of the cable?

I've answered your questions below, but the good news is that, in a 486 machine, it booted right away 😀

No "Press CTRL+A" message though.

I'll check it out in more detail once the 1542CF, spare EPROM chips and UV eraser arrive.

Brostenen, on the 486, even with all the shadow features disabled (Video, System, All devices), it still boots. So maybe there is something else going on?

soviet conscript wrote:

I have a 1542B that I was just messing with. I didn't have any issues with it detecting and booting. worked pretty much just as if i was setting an IDE drive up. It was only a 1GB drive though.

heres how mine is jumpered. The floppy controller on the card is disabled. I also originally had issues with a resource conflict with the sound card which I think i remember solving by changing addresses.

Thank you!

Apart from the VGA card and SCSI controller, no other cards are in the machine. I am using the Floppy interface on the Adaptec, works fine.

clueless1 wrote:

Did you try hitting CTRL-A repeatedly throughout the POST process? Maybe the message is going by too fast to see it.

Of course 🤣

brostenen wrote:

Have you enabled shadow memory in the computers BIOS? It will need that in order to boot.
Does the harddrive have the lowest SCSI Device ID? (can't remember if that is 0 or 1)
Have you terminated the end of the cable?

I remembered your advice of course! Drive is ID 0 and yes terminator resistors are installed.

Good to hear, that it is up and running. 😜
How much heat does the drive put out? My IBM 10.000rpm drives get seriously hot. 🙁
Therefor I am constantly looking into getting a 5400/7200rpm SCSI-II drive.
(Why did I not keep the 40mb drive I had years ago)

It's an old 500 MB drive with 50 pin connector. It's noisy, but not really hot to be honest. I don't have anything high end. Getting a 9 GB drive soon. It's 80 pin though, so I will be using an adapter. Plus another SCSI mystery device that I will reviewing at some point 😀

PhilsComputerLab wrote:

It's an old 500 MB drive with 50 pin connector. It's noisy, but not really hot to be honest. I don't have anything high end. Getting a 9 GB drive soon. It's 80 pin though, so I will be using an adapter. Plus another SCSI mystery device that I will reviewing at some point 😀

Oooh! Oooh! A SCSI flatbed scanner?

clueless1 wrote:

PhilsComputerLab wrote:

It's an old 500 MB drive with 50 pin connector. It's noisy, but not really hot to be honest. I don't have anything high end. Getting a 9 GB drive soon. It's 80 pin though, so I will be using an adapter. Plus another SCSI mystery device that I will reviewing at some point 😀

Oooh! Oooh! A SCSI flatbed scanner?

I have one of those, an old HP one. Been my workhorse for many, many years. In fact it's so old it was never supported in any Microsoft OS after NT4. Works fine in Linux though. 😀
Very good build quality, and resolution/color rendition is better than any of the crap you can buy in stores these days.

brostenen wrote:

Have you enabled shadow memory in the computers BIOS? It will need that in order to boot.

Now this is interesting, because on my 1520B adapter shadow RAM needs to be disabled for the BIOS and booting to work. Now it might just depend on the adapter model, but trying without enabling shadow RAM might be worthwhile.

Although I also remember trying that card on a AMD Duron system and not being able to get the hard disk detected at all (and no BIOS message) while it previously had worked in a 486...so maybe these cards are sensitive to global system speed?

It might be because of different controllers.
My card, 1542-C, has settings for memory space (example d800h or d400h) and I need to enable the same space in my BIOS in order for the card to work.
I can set it all by dipswitche, found on the card somewere.

One point with the ISA controllers is, that the BIOS on the card usually defaults to the controller to be at port 0x330h fixed. If the ROM find the controller it enables the configuration services etc.
If the controller is jumpered to another port then the controller still works, however no ROM services are enabled (e.g. booting from SCSI) since the ROM is programmed for the default port only. If another port should be used a different BIOS ROM has to be used (e.g. for controller at port 340h).