Re: AltairZ80 simulator updated

Barry Watzman wrote:

The 640k limitation was ENTIRELY in the hardware. The Heath/Zenith Z-100 allowed 768k of user RAM (it's video and bios used the last 256k), and it was running the same OS as the PC.

Later versions of OS/2 would run DOS in something like 704K,
not using the X'A0000' block normally reserved. In addition,
there was almost 64K more available at X'100000' due to the
way segment offsets were computed on later processors.

-- glen

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