[Simh] ALTAIR thinko?

[Clem Cole]

On Mon, Feb 2, 2015 at 10:16 AM, Bailey, Scott <scott.bailey at hp.com> wrote:

> Non-existent memory.  On the 8080, reads to non-existent memory
>       return 0377, and writes are ignored.
>

​That was definitely true and how the HW worked [although the comment
should have been 0xFF or actually $FF in Intel syntax - since the 8080s
were defined in hex not octal like PDP-11s).  There was no non-existent
memory trap for the bus, so the HW read the data back as 0xFF because of
TTL floating to high.

I do miss the Altair and Imsai machines in a strange sort of way ;-)

Clem
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