[comp.sys.apple] Problem using serial port firmware

lamb@soadc.enet.dec.com (brad lamb 13-feb-1990 0819) (02/13/90)

I need a little help with this problem.  I am writting an application in which
I need to send and receive from the serial port during a heartbeat interrupt.
The interrupt part is working fine (I think) but I am having a problem with the
serial port.  Since this is in an interrupt, I can't count on using any GSOS
calls.  That brings me to the serial port firmware, as described in chapter 5
of Apple IIgs Frimware Reference.  Unfortunately, no examples were given on how
to use the Pascal protocol and I am not enough of an assembler to figure it out.

First, could someone provide some samples of code using the Pascal firmware 
protocol, or a poiner to some samples?

Second, is there an alternative way (better) way of working with the serial 
port while in an interrupt?


Brad Lamb
Digital Equipment Corporation