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wirgeld23

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input from parallel port

Hello! can anyone tell me what's wrong with my code?  It's supposed to get input from my parallel port.  I compiled it with turbo c++.  I'm using windows me.

#include <dos.h>
#include <iostream.h>

main()
{
for( unsigned int i = 0; i < 256; i++ )
  {
  int x = inportb( 0x379 );
  cout<<x<<" ****"<<'\n';
  sleep( 1 );
  }
}

the output i get is:

120 ****
120 ****
... and so on...

this happens even though I put one of the input pins into high logic( 5V ).  Can anyone tell me what's wrong?  thanks!
Avatar of Mafalda
Mafalda

LPT1 data is at 0x378 ....
Avatar of wirgeld23

ASKER

i thought 0x378(data port) was for output and 0x379(status port) was for input?...(0x37A for control port)
Yes, the status ports are designed for input...
Are you sure that you are accesing the active parallel port.
In some PCs 0x378 is LPT2, 0x278 is LPT3 ... and 0x3BC is LPT1
Also, a good book for you:
http://www.lvr.com/parprtib.htm
i checked my parallel port address.  The i/o is in 378.  Does that mean I should use 378 even when inputting data?  By the way, what am I supposed to get when I use the inp function if I don't input anything?  and if I do input 5v in one of the input pins?
ps.  my parallel port is set to EPP.  I read that you can input to pins 2-8( data pins ) in EPP.  I tried it but nothing happens.
Avatar of Mayank S
I see that you've also posted the question under the 'Programming' section.

Please refer to:

https://www.experts-exchange.com/questions/20566532/input-from-parallel-port.html

where more comments have been posted for you.

Mayank.
No comment has been added lately, so it's time to clean up this TA.
I will leave a recommendation in the Cleanup topic area that this question is:

PAQ/Refund

Please leave any comments here within the next seven days.

PLEASE DO NOT ACCEPT THIS COMMENT AS AN ANSWER!

Tinchos
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Computer101
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