HP OpenVMS Systems

Ask the Wizard Questions

Passthru print queue

The Question is:

I need to send a binary graphics image to a Laserprinter connected to
a serial port on an Alpha. How does the port and que need to be set up
in order to pass the binary without having the data interpreted by
VMS?

The Answer is:

   One normally uses an encoding scheme that does not involve raw binary
   data over the serial connection -- Postscript can display bitmaps, etc.

   When raw binary data is used on a port, one must disable all in-band
   flow control, and this can lead to problems with the communications
   link.  When in-band flow control is disabled, the XON and XOFF flow
   control characters are treated as data.

   One uses SET TERM/pasthru (one `s') or (obsolete) /passall.  With the
   former, specifying /nottsync and /nohostsynch disables the flow control.