Programming HP Plotters over RS-232

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#217

From: Joel Spolsky
Date: Thu, 29 Mar 1990 03:29

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Hi yall, a quick question; we've got this HP Plotter attached to COM1
(over RS232) and I have tried to program it with

	plotter = fopen("COM1");
	fprintf (plotter, "...");

but every once in a while some buffer overflows and I get nasty DOS
"Write error on COM1, Abort Retry Ignore Fail" messages scribbled all
over my otherwise extremely beautiful VGA graphic screen.

What am I doing wrong? Do I have to write my own routines to write one
character at a time to the UART and check when it is ready for
another? will this solve my problem at all? or is there an easier way?

Many thanks,

+----------------+----------------------------------------------------------+
|  Joel Spolsky  | bitnet: spolsky@yalecs.bitnet     uucp: ...!yale!spolsky |
|                | internet: spolsky@cs.yale.edu     voicenet: 203-436-1538 |
+----------------+----------------------------------------------------------+
                                                      #include <disclaimer.h>

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From: spolsky-joel@CS.Yale.EDU (Joel Spolsky)
Newsgroups: comp.sys.ibm.pc.programmer
Subject: Programming HP Plotters over RS-232
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Date: 29 Mar 90 03:29:44 GMT
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