9

I'm trying to rescue an old DOS 6.2 application that originally ran on a 486 DX2 computer. I've moved the hard drive into a relatively newer Celeron 633, and everything seems to work fine except for when I try to print to the parallel port (LPT1) using any of the standard printing commands. The signal is sent to the printer, but the wrong characters come out on paper. Specifically:

0123456789 prints correctly.
áéíóú prints correctly.
abcd prints ☺☻♥♦
ABCD prints !"#$ (is 0x2 off)

The loaded console codepage is 850. The printer in question is an HP DeskJet 940C. Unfortunately I don't have a second parallel-port printer to test with.

Why would this change from one computer to the other when the OS is strictly the same, and how do I configure DOS to print correctly?

Thank you in advance.

Improve this question
3
  • 2
    If you print a test from the command line (e.g. "ver > lpt1"), does it print incorrectly? I didn't know an inkjet could survive for so long. :)
    – Jason
    Nov 8, 2013 at 17:28
  • 1
    You brave soul...
    – user62491
    Nov 8, 2013 at 17:34
  • Jason: Unfortunately yes, it prints incorrectly. I've tried piping to LPT1, the print command, and the application.
    – Alex J
    Nov 8, 2013 at 18:01

1 Answer 1

Reset to default
4

Try different settings for the parallel port in the BIOS of the new machine. Compare them to what the 486 supported (it might not tell you; you might need to find docs on the motherboard.)

Improve this answer
2
  • CMOS allows me a choice between Normal, EPP, ECP and ECP+EPP. ECP also lets me pick DMA 1 or 3. I've tried all of them, with different IRQ combinations, with always the same results.
    – Alex J
    Nov 8, 2013 at 16:26
  • 2
    Weird. The mapping of the characters is not consistent with a loose contact on the printer-port or in the cable. In that case the áé etc would be wrong too. By the way: Bios setting "Normal" would be best. The others are not really suited for Pentium and later hardware. (They were designed for VERY slow CPU systems. A 386 was already fast for them...)
    – Tonny
    Nov 8, 2013 at 17:08

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .