Have you tried VIDE-CDD.SYS or any other ATAPI drivers? IDE mode and the BIOS extension segment should expose ATA/ATAPI instructions to DOS without any SATA specific software. You can also try GCDROM.SYS which is SATA specific.

Hey

thanks for your answer. I have tried all of the drivers you mentioned without any luck. They're not crashing or anything, they just don't find an ATAPI device and thus don't load.

I suspect that the SIL3512 hooks the int13h BIOS routine to provide hard disk specific functions for drive C: but doesn't "emulate" a real IDE controller.

The NSSI tool (a diagnostics system info tool for DOS) for example does not detect any IDE drivers. Instead it lists the main drive under "Non-IDE".

Locutus wrote:

I suspect that the SIL3512 hooks the int13h BIOS routine to provide hard disk specific functions for drive C: but doesn't "emulate" a real IDE controller.

The NSSI tool (a diagnostics system info tool for DOS) for example does not detect any IDE drivers. Instead it lists the main drive under "Non-IDE".

here is possible three modes for disk subsystem:

Legacy IDE - up to 4 disks on 2 IDE controllers on irq 14/15 with addresses 1f0/170. also possible very rare config with more 4 disks on tertiary/quaternary controllers on ports 1e8/168. all ports in ISA i/o address space, so this must work with any drivers. good bioses also emulate this for sata.

Native SATA - unlimited number sata controllers on any irq with any addresses, a-la FF80. ports outside ISA i/o address space, so need rewrite drivers for scan upper i/o space, but commands for access to disk is not changed. poor bioses leave sata in this mode. uide/xide/xhdd/xdvd can help only with this issue.

RAID, AHCI and NVME - have nothing good for any OS. fully different protocols. incompatible. need special driver. Skylike and Ryzen platforms. Intel was release AHCI driver for CD/DVD-ROM under DOS - AHCI.SYS. its all.