tony@cosc.canterbury.ac.nz (03/20/91)
After many hours Reading TFM, soldering up new cables, etc, I worked out how hardware flow control for printers works on SunOS 4.1.1 I tried this out on a SS2 and an SLC, and they both worked. A Flame for Sun: why do they make it so hard to figure out their tty ports? Maybe I'm just stupid :-) Anyway, the information I gleaned might help someone else: 1. The cable (Sun Workstation end): Pin 2 = Transmit data from Sun (and to the printer :-) Pin 3 = No Connection; BAD, BAD crosstalk from TxD happens if you leave this line connected on long cables, as I found out :-( Pin 5 = Clear To Send from the printer. Positive (> 3V) = OK to send data, Negative (< -3V) = Stop sending data. Pin 7 = Signal ground Pin 8 (Carrier Detect) is strapped to Pin 20 (DTR from sun) The effect of this is to make CD permanently "on". EVEN IF YOU "stty clocal" YOU NEED THIS. Another 2 hours to find this out :-( Pin 8 won't work for flow control, BTW 2. Here is the "ms" (tty settings) field from my /etc/printcap. The important fields are crtscts and -ixon (see stty(1V)): ms=cs8,clocal,-parenb,cread,crtscts,ignbrk,ignpar,cstopb,\ -ixon,-tabs,onlcr,-echo: Hope all this is useful to someone. = Tony Dale (tony@cosc.canterbury.ac.nz) =