Parallel Port Problem!


New member
Yes! I know that parallel port connections are not suported but I was just playing a bit with the HD44780 based LCD while the 8051 is on his way...

Anyway.. the problem doesn't seem to be on the LCD or its wiring. I can send a few controls signals to the lcd by setting the right wires.

The problem seems to be with the LPT port and I thougth that maybe some one could help me.

It seems that the data pins DB0-DB4 on LPT are always on and DB5-DB7 are always off. I tried to use CFAH_WinTest: the signals E0, RS and RW I can sucessfully turn On and Off (measuring results with a multimeter). But with the Data Pins they always are Low or High as mencioned before?
Is it possible that I have fried my Parallel port? (Can't tell you how..) Any suggestion would be apreciated.

By the way:
I'm using Win98 in a P2XBL board.
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New member
Did you install the port95 driver?

Do you have any other software inflicting with it? (i.e. parallel port printer drivers)


New member
Yes I have on both machines, I'm going to check each parallel port's actual output with some software, you never know nowadays with some boards, the legacy ports can be total junk...Besides the machines I'm using are printing via a network print server so who knows???

Mainly IT I guess!!



All fixed...running the software right now on the Itron VFD...:D
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