🚀 go-pugleaf

From: dean@a.psy.cmu.edu (randall w. dean)

 I am having a minor problem with my VaxStation II (MicroVax II running
VMS 4.1M).  We have a Drv11J connected which is controlled by the Coninterr
driver.  The Drv11j is connected to a 1KHz clock which I have generate an
interrupt every micro second.  During interrupt, three buttons are polled
for change of state.  If a change of state occurs in any, a user context
Kernel mode AST is scheduled (using system internal routine EXE$DCLAST).
I have a test program which connects to interrupt and sits in a tight
loop printing out the contents of a register updated by the interrupt
routine.  If I hit a button, the AST fires as planned.  If I hit the buttons
about 10 times in rapid succession though, the system will crash with
a excpetion at ASTDEL or above (IPL above 2).  If I have the program sit
in a tight loop doing nothing, no matter how many times I hit the buttons,
the system won't crash.  Finally, regardless of the test program, in about
1 of every 5 times I run it (Exiting with ^Y) the keyboard for the 
Vaxstation becomes unreponsive (Interrupt disabled I suspect).  Reloading
the driver and restarting the DISPLAYMGR are of no help.  The system
needs to be rebooted.  Shutting down the system over DECnet with reboot
does work in reenabling the keyboard.

 It would be nice if we had the right level of software maintenence with DEC
to just ask them why there system flakes out when using supported hardware
and device drivers; unforunately...  

If anyone has any experience/suggestions in/for dealing with this, please
get in touch.

Thank You,

Randall Dean
Research Programmer
Carnegie-Mellon University
Phone: (412)578-3784
Arpa:  Dean@A.PSY.CMU.EDU
CCnet: Dean@CMPSYA