25 Dec
2010
25 Dec
'10
12:18 p.m.
On 25 Dec 2010 at 13:02, Eric Smith wrote:
Tony Duell wrote:
...and IOBYTE wasn't universally implemented among OEMs. It was an
optional feature of the BIOS in the early days of CP/M. I can
probably find some words in the System Alteration Guide to that
effect, if anyone's interested. Other than STAT and PIP, I'm not
aware of any standard CP/M utility that cares about it--or supports
the additional "extended" device names.
--Chuck
I beleive the historay can be traced back to the
MCS8i system.
This, > AFAIK, never had disks, and never ran CP/M. But it's
8080-based and > amazingly it has a CPM-like IOBYTE at location 3.
It's not that the Intel development systems had a CP/M-link IOBYTE.
It's that CP/M has an Intel MDS-like IOBYTE. Remember that Gary
Kildall wrote software for Intel before writing CP/M, and that CP/M
was written to run on an MDS