🚀 go-pugleaf

I've been trying to get some interrupt driven code to work
with the DigiBoard MC/8 board and not having much luck.  The
MC/8 board has eight serial ports on it plus some hardware that
provides a status port, which one can use to tell which port
generated an interrupt.

I have code (essentially the same as COMPKG2 from the Info-IBMPC
archives) that works fine with the regular AT bus DigiBoards,
and also works fine with the regular two PS/2 serial ports, but
it doesn't work with the MC/8.  (The MC/8 is the PS/2 MCA bus
equivalent of the DigiBoard Com/8 card).

What happens is that as soon as my code enables the Interrupt Enable
Register for transmit interrupts, the machine hangs.  It never
gets to the interrupt code.  The DigiBoard tech support folks don't
seem to know much.  Has anyone had this same problem and figured it
out?  I'd sure appreciate a clue.

Richard