[comp.sys.ibm.pc.hardware] Phoenix BIOS and IRQs

pjh@mccc.uucp (Pete Holsberg) (11/16/90)

Does anyone know if the Phoenix BIOS immediately enables interrupts at
power-on?  I have an AT&T 6386E/33 with a serial cable on COM2 that goes
to a 3B2/400 serial port that has a uugetty running on it--that is, it
is a bidirectional port driver.  When I cold boot the 6386, it runs at a
tiny fraction of its normal speed.  Eg., the letters "Phoenix" appear on
the screen one at a time with a 1-2 second pause between them!  It was
suggested that if the interrupts are not disabled and the BIOS sends
anything out the serial port, the 3B2 will respond by sending "login"
out the port.  This becomes a nearly deadly embrace!

I should point out that the 386 with the AMI BIOS does not do this.

Thanks,
Pete
-- 
Prof. Peter J. Holsberg      Mercer County Community College
Voice: 609-586-4800          Engineering Technology, Computers and Math
UUCP:...!princeton!mccc!pjh  1200 Old Trenton Road, Trenton, NJ 08690
Internet: pjh@mccc.edu	     Trenton Computer Festival -- 4/20-21/91