Printers, modems not working in OS 4

[Steve Jay]

There have been several queries in Sun-Spots recently about printers on
serial lines not working in OS 4.

There are major bugs in the drivers for serial ports in OS 4 and 4.0.1.
Among other things, XON/XOFF doesn't work, and modem control signal (DTR,
etc.) handling is wrong.  For us, this meant that our Postscript printer,
an HP Plotter, a 2400 baud Hayes modem, and a Trailblazer modem didn't
work.

The solution is to get the "serial patch tape" from Sun.  You should be
able to get it by calling 800-USA-4SUN.  Ours was labeled "yapt 5.4", for
"yet another patch tape 5.4", and we later got "yapt 5.5".  Either one
fixed all of our observed problems.

I'm told the patch tape is also available electronically via "uunet", but
I have no knowledge of how that works.

A temporary solution is to drive your important serial devices off of CPU
serial ports (ttya & ttyb).  Under 4.0.1, the CPU serial ports seem to
handle XON/XOFF correctly, allowing printers to work.  However, even the
CPU serial ports didn't handle DTR correctly until we installed "yapt
5.4", so we couldn't dial into a modem connected to a CPU serial port
(dialing out worked).

Steve Jay                       domain: shj at ultra.com
Ultra Network Technologies	Internet: ultra!shj at ames.arc.nasa.gov
101 Daggett Drive               uucp: ...ames!ultra!shj
San Jose, CA 95134		
408-922-0100

[[ There are Sun fixes on uunet, but I don't see anything that fits your
description.  Those on the Internet can anonymous FTP to "uunet.uu.net"
and cd to "sun-fixes".  Then retrieve the ASCII file "README".  It's all
explained there.  --wnl ]]