Eventually just took out my MS-DOS 5.0a disk image and am now using it to format the disk image. Then it's back to MS-DOS 6.22 to copy the OS and finally convert the disk image to a static disk image to copy over all files that were on the old disk image.
Still odd that MS-DOS 6.22 completely fails the FDC, but MS-DOS 5.0 reads it just fine.
Just finished generating a basic MS-DOS 6.22(nothing but the prompt) sys'ed hdd image of 2GB(Bochs/Dosbox format).
Edit: After looking for the problem that occurred with static/dynamic disk images, I've noticed that:
- The dynamic disk image header was incorrectly checked(size check), causing the disk to be formatted in the wrong format(compatibility format instead, so the old UniPCemu format incompatible with Bochs/Dosbox) and wrong CHS geometry to be reported to the OS(BIOS/MS-DOS).
- The static disk images didn't properly create metadata files(.unipcemu.txt and .bochs.txt) when converting dynamic disk images to static disk images, causing the format to be lost when reconverted into UniPCemu's dynamic disk image(.sfdimg) format.
I've managed to boot MS-DOS 5.0a properly from the XT boot floppy and fdisk/formatted the harddisk, but MS-DOS 6.22 doesn't seem to boot?
Edit: IBM AT with Intel Inboard AT seems to crash with a system board error?
Edit: It seems to program all DMA mode control registers for test mode instead of proper floppy write mode for reading sectors? Most DMA registers are filled with 0xAAAA?
The BIOS gives a 303-Keyboard or System unit error and 601-Diskette error? Anyone knows the cause?
Edit: Looking at a possible cause of the 601 error(E601) shows that the FDC might not finish initializing due to hdd testing failing(port 2f4 accesses)?
Edit: The AT 601 error seems to be because the Interrupt 13h Reset for the FDC is failing(AH=20h, while it expects 00h)? It's happening during the second 3C being written to the Diagnostic Port, so I've placed a breakpoint on that code, then single stepped down to the failing INT13h call(test2.asm, line 1169(verify status after reset)). That address corresponds to the BIOS execution at f000:00001260(real mode).
The attachment debugger.log is no longer available
Anyone can see what's going wrong there?
Edit: Since AH=20h it must be a FDC controller failure(I only see it resetting using the DOR from a hardware point of view, so maybe a processor error or forgotten handling of the FDC?