Lab 5

Due: Nov 8, 2000

Purpose: Introduction to Device Drivers in Linux

Reading: Sections 9.1, 9.2, and 11.13 of the SA-1100 Developer's Manual

For this lab, you are to develop and install a simple (non interrupt driven) Linux Device Driver on the CerfBoard's Linux OS for an ultrasonic range finder device. You will need to learn about:

•     The sonar device
•     How to make and install a Linux Device Driver (We will leave a good book on this in the Lab, and provide you with templates/instructions)
•     How to program the StrongARM processor in Kernel Space for device I/O (see CerfBoard specs, and SA1110 Specs above)

We are still putting the finishing touches on installing device drivers for the CerfBoard, so please start by getting your Sonar system to work with you 8051 processor. We will leave a copy of a good book on how to develop device drivers in the lab for you all to share.

Part 1: Hook Up and test the sonar with your 8051

We are still putting the final touches on the development environment for the CerfBoard system, so please start by hooking your sonar up to an 8051 and get it to work...you might as well use the serial I/O to send the distance results to the screen. Two extra points for demonstrating this in lab on 11/1/00. Watch out for power supply noise due to capacitive loading by the Sonar!!!

itches.

Part 2: Sonar Device Driver (See the guide written by Douglas)

Install your sonar onto the CerfBoard System. The CerfBoard has its own power supply, but MAKE SURE TO CONNECT THE SONAR AND CERF GROUNDS TOGETHER BEFORE TURNING ON POWER!! Refer to the CerfBoard hardware documentation and to the StrongARM documentation.  Pick two pins that are available on Port0 or Port1 of the Cerf break-out-board that correspond to GPIO pins on the sa1100. Connect INIT to one of these pins and connect ECHO to the other. Make sure to check the output enable and port direction settings of the DIP switch on the Intrinsyc break-out-board.

• Create and install the device driver for your sonar device. It does NOT have to be interrupt driven. We will get to that later.
• Test it out
• Write a user program that "forks" into at least two user processes, both of which attempt to open and continuously read the device. Make sure to print out a message about the distance measurement each time a successful read is performed. The printed message should include the process ID of the user process.
• Turn in the code for your driver, your user application, and screen shot of the output
• Demonstrate your system for Larry or Douglas.