Did you already try XCDROM.SYS from FreeDOS? It might not be so much that it doesn't do PIO, but that it runs only in PCI native mode and doesn't listen on the usual ports (1F0/170)

What PCI controller card are you using? Is it a RAID card or just a simple IDE card with no onboard BIOS?

What CD-ROM drive is it?

Hmmm, in DOS, drives automatically use a PIO mode. (unless it is quite a modern board with build in UDMA bios)

You don't really need to configure that.

The reason why the DOS drivers can't find it is because it is probably looking for a IDE controller at the standard IDE ports and Interrupts and the PCI card won't be compatible with that (generally).

You should put the CD-ROM drive on the onboard controller if possible, so DOS ATAPI drivers can find it.

XT-IDE is a good option, but won't let you use the advanced DMA modes on late 486 or pentium hardware. But if your motherboard configures drives for PIO mode 4, then you still get decent performance.

sbide.sys v2.0 is supposed to support DMA modes.

canthearu wrote on 2021-08-31, 01:26:

Hmmm, in DOS, drives automatically use a PIO mode. (unless it is quite a modern board with build in UDMA bios) […]
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Hmmm, in DOS, drives automatically use a PIO mode. (unless it is quite a modern board with build in UDMA bios)

You don't really need to configure that.

The reason why the DOS drivers can't find it is because it is probably looking for a IDE controller at the standard IDE ports and Interrupts and the PCI card won't be compatible with that (generally).

You should put the CD-ROM drive on the onboard controller if possible, so DOS ATAPI drivers can find it.

XT-IDE is a good option, but won't let you use the advanced DMA modes on late 486 or pentium hardware. But if your motherboard configures drives for PIO mode 4, then you still get decent performance.

I tried this, but it seems to be an either-or proposition. I can't get the onboard controller to enable if there the PCI card is installed. I thought XT-IDE UB doesn't work with the windows protected mode driver? Windows doesn't see the drive because the bios doesn't advertise it? Something like that?

jakethompson1 wrote on 2021-08-31, 01:19:

Did you already try XCDROM.SYS from FreeDOS? It might not be so much that it doesn't do PIO, but that it runs only in PCI native mode and doesn't listen on the usual ports (1F0/170)

I'll try FreeDOS when I get home. I didn't think to try that.

Yeah that makes sense, now that you say it like that. Looks like I might need to get an ISA native card. It sucks because the onboard controller is an OPTi VESA Local Bus chip -- the BIOS is just trash and can't deal with big drives. I could use an overlay, I suppose...

cyclone3d wrote on 2021-08-31, 01:20:

What PCI controller card are you using? Is it a RAID card or just a simple IDE card with no onboard BIOS?

What CD-ROM drive is it?

It's a simple IDE card but does have a Promise BIOS onboard, but there isn't any key combo at boot time to configure the card. It just autodetects whatever is plugged into it. The CD drive is a 24X HP-branded unit manufactured by Hitatchi (CDR-8330)

aspiringnobody wrote on 2021-08-31, 01:31:

I tried this, but it seems to be an either-or proposition. I can't get the onboard controller to enable if there the PCI card is installed. I thought XT-IDE UB doesn't work with the windows protected mode driver? Windows doesn't see the drive because the bios doesn't advertise it? Something like that?

You need to configure a drive type in the BIOS (the maximum size the BIOS detects is fine) ... XT-IDE will take over actual real management, and windows will notice the drive exists properly and it works fine.

I have multiple windows systems running XT-IDE.

aspiringnobody wrote on 2021-08-31, 01:31:

jakethompson1 wrote on 2021-08-31, 01:19:

Did you already try XCDROM.SYS from FreeDOS? It might not be so much that it doesn't do PIO, but that it runs only in PCI native mode and doesn't listen on the usual ports (1F0/170)

I'll try FreeDOS when I get home. I didn't think to try that.

Yeah that makes sense, now that you say it like that. Looks like I might need to get an ISA native card. It sucks because the onboard controller is an OPTi VESA Local Bus chip -- the BIOS is just trash and can't deal with big drives. I could use an overlay, I suppose...

You don't need to switch to FreeDOS; just try the XCDROM.SYS driver from:

https://www.ibiblio.org/pub/micro/pc-stuff/fr … om/xcdrom22.zip