LPT interface

[xxxx]

when i run this code:

     mov ah,0
     mov al,41h
     mov dx,0
     int 14h


nothing happens.isn't it suppose to print a character?what went wrong?my OS is windows XP.


thanks

[MichaelW]

AFAIK, that will generally work only for an older printer and a parallel port connection. Many/most newer printers have much greater capabilities than the older printers and must therefore use different command codes. The Windows 9x drivers for my ~7 year old HP DeskJet 1000C provided a "DOS personality" that would allow the printer to emulate an older printer, but the Windows 2000 drivers that I am currently using do not provide that capability.

You should be able to find some relevant information here (scattered across multiple sites):

http://www.columbia.edu/%7Eem36/wpdos/#anyprinter

[TRELVIS]

I had the same problem. was trying to control a couple of leds from the printer port on an old pc running windows me the program would work.

then transferred the file to my laptop which was running windows xp this world not work.

what was the problem ?

well it goes like this when trying to run dos console under xp it won`t let you access the port due to windows.
you dont have the write access level.
your program is working but windows is stopping you...

to get around this problem I found a program called userport found at http://www.embeddedtronics.com/design&ideas.html
this will open the I/O ports that you want.

hope this will help it did the job for me.