Date   : Sat, 16 Sep 1989 20:19:25 GMT
From   : ogccse!blake!callisto@ucsd.edu (Finn)
Subject: MEX using MP/M

In article <1832@sactoh0.UUCP> ianj@sactoh0.UUCP (Ian R. Justman) writes:
>Has anyone used MEX with MP/M?  I'm currently doing it, but I can't
>do any other tasks otherwise I will lose characters.  I'll probably
>have to write some sort of interrupt driven routine, but MP/M needs
>interrupts in order to process calls from other consoles.  Any help
>on this matter will be definitely appreciated.

 I used MEX with MP/M on an Altos 580 for quite some time, and found:
 Mex worked fine up to about 1200 baud, then gave up and lost characters.
 Sometimes, particularly after using x-modem, a "phase of the moon"
 type error caused mex to lock up that user when exiting to system.
 Sometimes the problem could be solved by killing the process from another
 terminals, and sometimes it was necessary to re-boot the machine.  I
 suspect this resulted from mex writing into the common memory above
 C000.