root42 wrote on 2022-07-04, 14:24:
But even the IBM PC/AT came with ROM BASIC, no? Let's fire up our machines and check if there is really something useful in the 32K block at 0xf600 😀
Ok, I had to be more precise in AT definition 😀 IBM 5170 (which I don't own) should have ROM BASIC.
The 'generic' 286-based PC I have has single 64KB BIOS chip, it has shadow ram option for the entire 64KB range.
The memory content at segment 0xF600 is not even a code but parts of the AMI BIOS gui resources - tables/strings.
My point is that if you need to bring the ROM BASIC into computer via ISA bus, that hints there are no provisions for ROM BASIC chips on the motherboard, and it's likely this is not the IBM that had ROM BASIC address range decoded and routed for that chip only, and such PC has that region physically taken by a single motherboard bios.