Parallel port access


Thread Starter

Pratyush Lal

My first time programming. Need to program a paralle port to control a 3 axis cutting platform.
any help would be thoroughly appreciated

We need more info. What OS are you using? What programming language(s)? How fast do the ports need to change? How many bits? Is there any handshaking? Is this a regular "PC" parallel port, or an I/O card? Is it bidirectional,
or unidirectional?

Willy Smith
Numatics, Inc.


Rodney Stevens


Are you talking about low level programming of the port ie inp oup etc in 'C'
Or have you got a program that uses the parallel port and you want to know how to use the commands.

You are asking for the world, but giving nothing in return. How about some more information.

Rodney Stevens
CSIRO Minerals
Ph. 61 2 97106701
Fax 61 2 97106789

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Hello Pratyush,

I hope you are talking plain about controlling a device which expects some commands, does some mech activity, and gives back responces to your commands, in a particular protocol.
If you are talking about a ibm compatible pc's parallel port, you can develop this device interface in C programming language.
If you want ease and speed of developing a testing program, start making a test prototype using VB on Windoze. Later on you can code in C using unix/win as the base os.
If only you could give more details......
All the Best

Christopher Williams


Maxim/Dallas Semiconductor have an application note of a data logger connected to a PCs parallel port. The program is a quick basic (DOS) program but I figured you might be able to use the source code to roll your own version for your CNC application. Unfortunately you can not directly manipulate a parallel port in Win98/NT (unless you get a parallel port driver written in C - this would take a few sleepless nights and about a case of mountain dew).

app note web page is at:
good luck!

Curt Wuollet

Why not simply use EMC from NIST. It's free, supports all sorts of nice features including simulation and g-code and is already proven.
At the very least you could use their parallel port driver.



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