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PCx86 Debugger Update
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@jeffpar jeffpar released this 23 Jul 19:50
· 2998 commits to master since this release
v1.23.2
1f3f394

This release (v1.23.2) was created simply to fix a problem with one of the Debugger commands in the PCx86 emulator; specifically, the Load ("L") command. When I changed one of the Disk Controller interfaces, I neglected to update the Debugger, so the Load command had been completely broken for a while.

What is the Load command, you ask? It's similar to the "L" command in the DOS DEBUG utility, which loads sector(s) from a disk into memory. For example, L 0:7C00 0 0 1 loads the contents of drive 0, sector 0 (for a total of 1 sector) into memory at address 0000:7C00 -- which is exactly what the ROM BIOS does when attempting to load and execute the boot sector from a disk in drive A.

After issuing that command, you could in theory set the CS register to 0 and the IP register to 7C00 and start executing the boot sector with the "G" command. However, unless you've let the ROM BIOS run first, the interrupt vector table (IVT) and ROM BIOS data areas will not be properly initialized, so your attempt to manually load and execute the boot sector will likely crash and burn.

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