ColdFire/68K Microcontrollers and Processors中的主题 Re: [Lite5200/Linux] Setting on-board LEDs

[Lite5200/Linux] Setting on-board LEDs

michael_wahler — Tue, 22 Jun 2010 15:40:03 GMT

Hi everyone,

I used LTIB to build a Linux kernel for the Lite5200 board. The Linux kernel boots without any problems and I can run a hello world program that I compiled with LTIB's gcc toolchain.

What I would like to do now is to switch the general-purpose LEDs on the board on and off. However, I do not have any experience in hardware programming. The user manual says: "General purpose LEDs have been provided for debug and development purposes. The LEDs are driven by an inverting buffer connected to the MCU pins described in the following table", followed by a table in which LED 1 is mapped to the IRDA_RX pin of the CPU. How do I find the address of this buffer in my code?

Best regards

Michael

Re: [Lite5200/Linux] Setting on-board LEDs

J2MEJediMaster — Wed, 23 Jun 2010 20:57:31 GMT

If you are building the project using the CodeWarrior wizard, the wizard should have generated a processor-specific header file that contains the mappings of variable names to peripheral registers, which in turn drive the pins. Look for a header file the uses the CPU's name or board's name, say Lite5200.h. In there you shoud find the variable name IRDA_RX, and what address that is associated with it. To write to the pin, you have to set it as an output (if it is a general-purpose I/O pin that could be an input or an output), then write a bit using IRDA_RX as the reference to the register.

Look at some of the example programs that should have come with the board's CD. There is usually a simple example program that blinks the LEDs that you can study and learn.