On Mon, Feb 2, 2015 at 10:16 AM, Bailey, Scott <[email protected]> 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
_______________________________________________ Simh mailing list [email protected] http://mailman.trailing-edge.com/mailman/listinfo/simh
