tschutte@isis.cs.du.edu (Tom Schutter) (03/12/91)
I am trying to hook up a HP LaserJet III to a Sun SparcStation and I have a few questions. The Sun doc says that "Sun serial ports have RS-232-C cabling conventions, but use RS-423 signaling." The LaserJet III doc says that the printer can be configured for RS-422A. I have successfully connected the SparcStation to an IBM-PC with a null-modem cable and have had no problems. I was blissfully unaware of the "RS-423 signalling." I have been partially successful connecting the SparcStation to the LJ-III. Apparently I have one-way communication from the SparcStation to the LJ-III. But the LJ-III cannot send x-on and x-off signals back to the SparcStation. Setting the baud rate to 1200 results in a slow but workable solution. The LJ-III doc indicates that both RS-232-C and RS-422A use pin 3 to receive data, but with RS-422A, the signal is "inverted". Questions: Why did the null-modem cable to the PC work? How do the RS-422 and RS-423 standards relate? What would be the correct cable between the SparcStation and the LJ-III? Thanx, Tom
hardy@golem.ps.uci.edu (Meinhard E. Mayer (Hardy)) (03/12/91)
Try switching off the Robust XON (default setting on the serial port) on the LJ; I did this with a NeXT and it reduced the timeouts at 9600 bd to a bearable level. Hardy -------****------- Meinhard E. Mayer (Prof.) Department of Physics, University of California Irvine CA 92717;(714) 856 5543; hardy@golem.ps.uci.edu or MMAYER@UCI.BITNET