NetBSD master CVS tree commits

[source%NetBSD.ORG@localhost]

mycroft
Sun Jun 15 04:19:04 PDT 1997
Update of /cvsroot/src/sys/dev/isa
In directory netbsd1:/var/slash-tmp/cvs-serv17475

Modified Files:
        com.c comvar.h 
Log Message:
Implement a better backpressure mechanism so that data is collected
in the driver's buffer if the tty buffer is full.  If the driver's buffer
becomes full, turn off receive interrupts until it drains a bit.