3 ms·
That wouldn't have worked, the point was to pack data in memory. Even on 64kb computers, MS-DOS 1.x loaded .COM files at the bottom of available memory and allo
by bonzini 4mo ago
That wouldn't have worked, the point was to pack data in memory. Even on 64kb computers, MS-DOS 1.x loaded .COM files at the bottom of available memory and allowed using the "familiar" CALL 5 interface even if the program was not loaded at physical address 0x100 (which is part of the interrupt table on x86). MS-DOS 2.x augmented that with TSR (terminate and stay resident) programs that could relocate themselves to use the minimal amount of memory at 16-byte offsets.
The 68000 was a complete break so it opted for relocatable code (which also needed more registers, and in fact the 68k had 16 instead of 8).