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Writing to the parallel port on Win32

Posted on 1998-02-27
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Last Modified: 2013-11-20
I want to to hold a value on the parallel port. In DOS, i just had to "outport" to the lpt address, while in Win32 ( Nt workstation )it is a bit more complecated i guess.
So far i was abble to open the file \.\\lpt for reading and writing ( CreateFile ), but wheneven i try to write, WriteFile failes ( although GetLastError claims that the operation completed successfuly ) and nothing apears on the parralel port.  
Does anybody know how to configure the parallel port ( maybe its a control flow issue? ) - is it done in the same bizzar way like the serial port?  How can i realy complete this simple and rather stupid operation successfuly?
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Question by:shaig
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jhance earned 50 total points
ID: 1316611
Using CreateFile doesn't open the port itself but rather the LPT port driver.  The port driver is designed to run a printer, so it wants something out there that "talks" like a printer.  If you need to do some sort of custom I/O to a port, you need one of two things, a VxD under Win95 and/or a NT Device Driver under NT.
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by:shaig
ID: 1316612
Is there a hardware  workaround, like connecting one of the parallel port pins to another ( similar to 3 pin serial connections - elimination of control flow ).
Sorry,
not realy an inteligent question, but i havne't got the time to explore this issue deeply.
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