27 Sep
2015
27 Sep
'15
9:44 p.m.
On 9/27/2015 7:30 PM, Eric Christopherson wrote:
On Sun, Sep 27, 2015, Jay Jaeger wrote:
No, not that I recall. That would have taken additional hardware for a
timer interrupt, at the least, and my Altair never had that. I recall
pipes being done as files, ala Mini-Unix.
JRJ
On 9/27/2015 12:30 AM, Eric Christopherson
wrote:
Did it have multitasking?
On Tue, Sep 22, 2015, Jay Jaeger wrote:
I'm not surprised, as it was never available as a product. I originally
inquired about it after an article about it in the BDS C User's Group
newsletter, and talked with Ed Ziemba, and he agreed to send me a copy
to play with / test. I tested a few versions before Ed Ziemba's
passing, and did some work on programs like icheck/ncheck/dcheck.
It was an operating system, not a layer on top of CP/M, although it did
use the CP/M BIOS calling conventions for the I/O layer. And, until you
got your own BIOS integrated into your copy of MARC, it could boot by
starting up a CP/M program on top of your existing BIOS, which was
termed a "parasitic boot". (BTW, My memory of that acronym is "Machine
Assisted Resource
Coordinator", a small-sized Unix work-alike developed by Ed Ziemba (RIP)
using Leor Zolman's BDS C compiler).
I'm having trouble finding much about this system; most of it is on your
web page and the Wikipedia page for BDS C, which appears to borrow quite
a bit from your page. Was MARC an OS itself, or a Unix-like layer on
CP/M? Is it available to download and play with?