I/O port accessing
Posted on 2003-12-07
I am a beginner at writing Linux dev drivers. I am facing problem while trying to compile and install the below simple module. The error is, "inb","outb" and
"--check_region" can't be resolved.
The code is
outb((unsigned char)"a", 0x23c));
printk("<1> The data at port is %d",inb(0x23c));
I am using gcc -O to compile. and insmod to install the module using the object code. Please remember that I am a beginner and would appreciate an explaination as detailed as possible. All I am trying to do is get familiar with the idea of reading and writing from IOPorts. If you can provide some information on this, it will be much appreciated. I eventually want to learn how to write a device driver in Linux and I am using O'reilley publications' "Linux Device Drivers" and it is not particularly helpful for rank beginners.