magnetic card reader prog.

[Unregistered]

I need to write a program that will read
magnetic cards and display the card code
on the screen in binary format (1's and 0's).
The signal from the card reader is connected
to the parallel port and can be read in
from address 0x379.

This is program that I have written but I'm
not sure if it works or not. If it does not work
I will not have time to fix it so it must
work the first time. If something is wrong with
the program can someone please tell me.


#include <stdio.h>
#include <conio.h>

void main()
{
char cls,rcp,prevCls=0,prevRead=0;
int in;

do
{ in = inp(0x379);

cls = (in & 0x80);
rcp = (in & 0x20);

if (!rcp && cls && prevRead)
printf("%d",(in >> 4) & 1);
else
if (!cls && prevCls)
printf("\n\n");
prevRead = rcp;
prevCls = cls;

} while (!kbhit());
return 0;
}

[Shadow]

> void main()
> return 0;
The first one makes the second one useless I hope you know.

[MethodMan]

If you have a function of type void(), the return type is void.. There is nothing to return. If you made main as just main(), that would make much more sense..

And why are you so restricted on your time limit?

[quzah]

This is program that I have written but I'm
not sure if it works or not. If it does not work
I will not have time to fix it so it must
work the first time. If something is wrong with
the program can someone please tell me.

That's pretty funny. You want to write a program that will read from a parallel port (ie: stream) and read the 0s and 1s and give you whatever it is you're looking for on the first compile. HAHAHA. Forgive me while I bust a gut. HAHAHAHA

Seriously.

HAHAHHA.

No, I'm really serious this time...

The signal from the card reader is connected
to the parallel port and can be read in
from address 0x379.

What OS is this supposed to run on? Depending on your OS, you cannot just directly access the hardware. Furthermore, You can't just (to my knowledge) grab some random address treat it like a character pointer or something.

You should have to be using functions like read or fread to read from the stream. Keep in mind, you parallel port is not just some memory address (again, to my knoweldge) that simply hold all pending input in some character array / buffer some place that you can simply access.

You have to open the stream for reading and read from it using the correct functions. As far as I know, and I'm not claming to know everything about hardware, you can't just simply pull some wild address out of a hat and treat it as a buffer.

Quzah.

[dv007]

I am really curious what your program's defined problem and what platform(Windows, Unix) your program will run on? Does it involve with IO address mapping or something else? As you might know that writing a program to interfacing with HW(nuts and bolts) need to be well define its hw architecture and requirements. Here is the website that I think might helpfull to
your project. http://ee.cleversoul.com/lcd_project.html
Good luck!
DV007

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