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Did any x86 CPU optionally trap unaligned access?
x86 CPUs have always supported unaligned load/store.
Early RISC CPUs didn't. So imagine writing portable code on a 386. It seems to work fine, but how do you know you haven't accidentally misaligned ...
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14
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What manages Upper Memory Blocks (UMBs) in MS-DOS?
I had always assumed that EMM386.EXE was responsible for managing the Upper Memory Blocks - UMBs - the memory space between 640KiB and 1MiB in real mode x86. For example, on MS-DOS 6.22, help emm386....
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