Are there any C coders out there that have solved the printer interface
under QNX4, with or without the spooler???
We have a PIII at 400MHz connected to a HP Deskjet 810 printer. We are
trying to get control over the printer from C code. If we do a
system(“pr filename”). The amber light comes on any we must press the
amber button to get the page to print. If there are two pages we have
to manually press the amber button for each page. The only difference
when we run the spooler is it works slower, a lot slower.
We have tried cp to the port, pr and opening the port and writting
directly to it.
Does anyone have any ideas?
Thanks,
Larry
I think generally, not having experience with the 810, that the amber
light means there is a partial page sitting in the printer buffer
waiting for printing. When you press the amber button, that tells the
printer to go ahead and print the partial page anyhow. This partial
page problem exists with printers that must have the full page before
they start printing. With line oriented printers, this is not a
problem as the printer just prints the number of lines received.
I would suggest that part of your problem is that your printing
program is not generating a final form feed to let the printer know to
go ahead and print the page. I have a NEC laser printer and have had
similar problems with it.
I don’t know why you would have to press the amber button for each
page of multiple pages unless that pages are somehow in different
printing sessions allowing the printer to wait for more data for the
first page and somehow holding off the 2nd page. (This is a wild
guess–I really don’t have a solid idea here.)
I have used the qnx tcpip spooler to print to a postscript printer
(requires the full page before printing) and it works fine.
Hope this helps,
Greg Laird
On Tue, 13 Mar 2001 15:08:10 -0600, “Imagine, Inc”
<imagine@galstar.com> wrote:
Are there any C coders out there that have solved the printer interface
under QNX4, with or without the spooler???
We have a PIII at 400MHz connected to a HP Deskjet 810 printer. We are
trying to get control over the printer from C code. If we do a
system(“pr filename”). The amber light comes on any we must press the
amber button to get the page to print. If there are two pages we have
to manually press the amber button for each page. The only difference
when we run the spooler is it works slower, a lot slower.
We have tried cp to the port, pr and opening the port and writting
directly to it.
Does anyone have any ideas?
Thanks,
Larry