The ideas which came flowing to my mind without significant thought were:

1) Could the hardware on this particular 1542CF card require a specific BIOS revision? I have a few of these cards and have never tried updating the BIOSes to the latest ones.

2) Does your motherboard have a working real-time clock battery? Is the time kept after a day of being turned off? Are the CMOS settings kept after a day of being turned off? Some motherboards will keep settings and time for many hours without a working battery. Must have some built-in capacitance or something similar.

3) Didn't a user post the MR BIOS for the opti 391 here already? Re: Best 386 Motherboard? Try it!

4) Did you try using the 1542 in every ISA slot? From my experience, some cards only like to work in some slots. Not sure why, but that seems to be a repeatable problem with some board/card combinations

5) You mentioned 1542CF. I think mine are 1542CP. What is the difference between the F and the P and do they use the same BIOSes and have the same hardware onboard?

feipoa wrote:

The ideas which came flowing to my mind without significant thought were: […]
Show full quote

The ideas which came flowing to my mind without significant thought were:

1) Could the hardware on this particular 1542CF card require a specific BIOS revision? I have a few of these cards and have never tried updating the BIOSes to the latest ones.

2) Does your motherboard have a working real-time clock battery? Is the time kept after a day of being turned off? Are the CMOS settings kept after a day of being turned off? Some motherboards will keep settings and time for many hours without a working battery. Must have some built-in capacitance or something similar.

3) Didn't a user post the MR BIOS for the opti 391 here already? Re: Best 386 Motherboard? Try it!

4) Did you try using the 1542 in every ISA slot? From my experience, some cards only like to work in some slots. Not sure why, but that seems to be a repeatable problem with some board/card combinations

5) You mentioned 1542CF. I think mine are 1542CP. What is the difference between the F and the P and do they use the same BIOSes and have the same hardware onboard?

Ding! Ding! Ding! We have a winner! I had read somewhere that newer BIOSes worked fine on older hardware, so naturally I flashes the latest version (v2.11) onto my card. I just tried flashing v2.01, which I believe is what originally shipped on the card and everything appears to be working perfectly! Apparently this card (1542CF) had three BIOS versions: v2.01 (1993), v2.10 (1994) and v2.11 (1995). I suspect maybe there is a minor hardware difference between revisions that caused the issue.

As for #5, I'm not sure what the difference between CF and CP are. According to Microsemi's site the cards have the exact same features, however, looking at pictures of the two cards it seems the layouts are a bit different (with the same basic components). The CP also seems to have later versions of firmware (the newest I can see being (C) 1997). Adaptec was famous for having a ridiculous number of product variations, so who knows!

Oh, and the OPTi 391 BIOS you mention in point #2 is for a 486 board. That same user *also* has a 386 OPTi 391 based board that's more or less identical to mine; he just hasn't had a chance to grab the BIOS from it yet. I'm curious how many more options it has compared to the AMI 386 BIOS on my board, which is *very* limited (there's hardly any chipset options).

But man, I really like this Adaptec card. Floppy access is a lot faster compared to my generic ISA IDE/Floppy card. Timing FreeDOS's kernel loading sequence from a boot floppy the Adaptec Card loads it twice as fast!

Thanks for the help!

Nice to hear that you got it working fine now.

A MR BIOS designed for an OPTI 391 w/486 should work on an OPTI 391 w/386.

On my system, I didn't notice any speed advantage when using the floppy controller on the 1542.

The 1542CF uses a centronics connector, and the 1542CP uses the HD50 connector. Other than that, I believe they are pretty much the same.

feipoa wrote:

Nice to hear that you got it working fine now.

A MR BIOS designed for an OPTI 391 w/486 should work on an OPTI 391 w/386.

On my system, I didn't notice any speed advantage when using the floppy controller on the 1542.

I tried it last night, but sadly the MR BIOS for that OPTi 391 486 board doesn’t work on my 386 board (I didn’t have high hopes, but it was worth a shot); no POST beeps, no display, nothing.

The AHA-1542 has an N82077SL floppy controller, which was one of the best standalone floppy controllers. It runs at a maximum speed of 1mbps and supports all floppy formats, including 2.88MB ED drives. So, I’m not surprised it’s a lot faster than the Goldstar IDE/Floppy chip on the old card I was using. I imagine the AHA-1542 wouldn’t be much better than the floppy controllers that started being integrated into the chipsets of 486 and Pentium era boards, but compared to the controllers integrated into the “Super I/O” and Floppy/IDE ISA card’s that were common in the earl 90’s it should be faster.

I’m so happy to at least have this build up and running.

386DX/DXL-40
OPTi 391 Chipset Motherboard
64KB 15ns Cache
4MB 70ns RAM (I have 16MB 60ns RAM on the way).
1.44MB 3.5” Floppy Drive
1.2MB 5.25” Floppy Drive
4GB 10k RPM Seagate Cheetah SCSI Drive (On a 5.25” to 3.5” rubber mount to minimize noise and absorb shocks during travel.)
Adaptec AHA-1542CF
Cirrus VGA LCD Controller w/ 10” Grayscale LCD
3Com EtherLink III
2xSerial 1xParallel Ports

Now I just need to put a decent sound card in and I’ll be set (I’ve already integrated some speakers into the case). I’m also working on replacing the grayscale LCD with a more modern color one (with a LVDS to VGA board) so I can use any VGA controller. 😀

I have experienced a few floppy controllers which did respond at about half the speed of those found in PCI-486 systems. I wasn't sure if it was just the start-up response, or throughput in general. I never bothered to time it.

That's unfortunate about MR BIOS. Hopefully the proper MR BIOS will emerge. The good news about MR BIOS is that I just tested on my UMC 481/482 motherboard and it automatically detects a PS/2 mouse when you plug in a PS/2-KBC adapter module. See here: Native PS/2 mouse implementation for 386/486 boards using the keyboard controller . So, no need to run a driver file or modify the BIOS.

Too bad I just found this thread. I literally JUST went through everything you had trouble with, with the exact same hardware. Oh well, least you fixed it.

Sorry to necrobump this, but where can one source 154x bios images? Adaptecs website does not have them and I can’t get my adapter to boot to the SCSI hard drive.

timb.us wrote on 2018-02-25, 12:18:

Ding! Ding! Ding! We have a winner! I had read somewhere that newer BIOSes worked fine on older hardware, so naturally I flashes […]
Show full quote

feipoa wrote:

The ideas which came flowing to my mind without significant thought were: […]
Show full quote

The ideas which came flowing to my mind without significant thought were:

1) Could the hardware on this particular 1542CF card require a specific BIOS revision? I have a few of these cards and have never tried updating the BIOSes to the latest ones.

2) Does your motherboard have a working real-time clock battery? Is the time kept after a day of being turned off? Are the CMOS settings kept after a day of being turned off? Some motherboards will keep settings and time for many hours without a working battery. Must have some built-in capacitance or something similar.

3) Didn't a user post the MR BIOS for the opti 391 here already? Re: Best 386 Motherboard? Try it!

4) Did you try using the 1542 in every ISA slot? From my experience, some cards only like to work in some slots. Not sure why, but that seems to be a repeatable problem with some board/card combinations

5) You mentioned 1542CF. I think mine are 1542CP. What is the difference between the F and the P and do they use the same BIOSes and have the same hardware onboard?

Ding! Ding! Ding! We have a winner! I had read somewhere that newer BIOSes worked fine on older hardware, so naturally I flashes the latest version (v2.11) onto my card. I just tried flashing v2.01, which I believe is what originally shipped on the card and everything appears to be working perfectly! Apparently this card (1542CF) had three BIOS versions: v2.01 (1993), v2.10 (1994) and v2.11 (1995). I suspect maybe there is a minor hardware difference between revisions that caused the issue.

As for #5, I'm not sure what the difference between CF and CP are. According to Microsemi's site the cards have the exact same features, however, looking at pictures of the two cards it seems the layouts are a bit different (with the same basic components). The CP also seems to have later versions of firmware (the newest I can see being (C) 1997). Adaptec was famous for having a ridiculous number of product variations, so who knows!

Oh, and the OPTi 391 BIOS you mention in point #2 is for a 486 board. That same user *also* has a 386 OPTi 391 based board that's more or less identical to mine; he just hasn't had a chance to grab the BIOS from it yet. I'm curious how many more options it has compared to the AMI 386 BIOS on my board, which is *very* limited (there's hardly any chipset options).

But man, I really like this Adaptec card. Floppy access is a lot faster compared to my generic ISA IDE/Floppy card. Timing FreeDOS's kernel loading sequence from a boot floppy the Adaptec Card loads it twice as fast!

Thanks for the help!

What makes you think the issue is your card's BIOS? I see you are using a SCSI2SD device. Try a regular HDD first. If that works, then troubleshoot your SCSI2SD settings. I also did not get SCSI2SD working on the first try.

The latest BIOS supports 8GB and not only 2GB, maybe this matters.
See attachment.

I suppose that assumption arises from the idea that I can boot from a floppy and see the SCSI2SD... but can't boot directly to it.

If required: Any recommendation on a HDD to meet this purpose? I'll have to buy one.

feipoa wrote on 2021-11-19, 06:25:

What makes you think the issue is your card's BIOS? I see you are using a SCSI2SD device. Try a regular HDD first. If that works, then troubleshoot your SCSI2SD settings. I also did not get SCSI2SD working on the first try.

Update, in my case, I had to run FDISK /mbr after booting from a dos disk. Even though I had partitioned the disk before, there was no master boot record. I'm going to write an article about my process for posterity sake. Thank you all for your help.

guyewhite wrote on 2021-11-19, 23:40:

Update, in my case, I had to run FDISK /mbr after booting from a dos disk. Even though I had partitioned the disk before, there was no master boot record. I'm going to write an article about my process for posterity sake. Thank you all for your help.

Good to hear you found the problem. Are you going to upgrade the SCSI card's BIOS anyway?

Absolutely! Don’t you think a good idea?

feipoa wrote on 2021-11-20, 13:58:

guyewhite wrote on 2021-11-19, 23:40:

Update, in my case, I had to run FDISK /mbr after booting from a dos disk. Even though I had partitioned the disk before, there was no master boot record. I'm going to write an article about my process for posterity sake. Thank you all for your help.

Good to hear you found the problem. Are you going to upgrade the SCSI card's BIOS anyway?

Because I don't know your skill level, it would be inappropriate for me to estimate your probable risk of destruction. Let me know how the upgrade goes.

What should go wrong flashing a pair of 27256 and trying them out in the controller?
To my knowledge the 1542 have no EEPROM.
The "F" means "fast", in the sense that the BIOS is copied into an onboard RAM which is then used for the BIOS routines instead of the slow ROMs.
So this also means, the 1542CF BIOS must not be shadowed!