Short Version

Using EB40A evaluation board.
Trying to interface with LEDS/SWITCHES.
Programming in Assembly.
Is there any way to directly interface with LEDS/SWITCHES?
How do I talk to the LEDS/SWITCHES

Long Version

I am new to the ARM. I am progamming in Assembly and trying to interface with the LEDS and SWITCHES.
I would like to work on polling first then work up to interrupts.

I have been over the LED SWING and INTERRUPT applications you can download, and there is too much information
for me to sort through.

So here's my question:

Do you have to include all the libraries, files etc... that come with the LED SWING and INTERRUPT applications,
or is there a simper way to light a LED with a switch?
(ie) direct/indirect addressing

Thanks in advance for your help.

Ethan

Hi Psyberbob,
i do not have this board, but the things to get a led on/ off, which is connected to a gpio pin, is basicly the same for all controllers.
1. set the direction
2. set/ clear the pins (some controllers have one register for setting/ clearing, some controllers have separate registers for setting and clearing)

The source code you mean (i think) includes all the the things to power on the system (interrupt table, memory initializing and preparing the C-startup). This can be very different between the controllers. Atmel startet at very low frequency, which is a good solution for saving power. But you have to do more at startup (setting the frequency to higher values).

After the startup is done, you can control the led like described above. Note that the AT91 chips use one register the clear (level zero) and an other register to set the output. In a third register you can sample the actual status.

I suggest start programming, using the debugger (mostly Angel) inside. To connect it, you need the ARM SDK (it is quite extensiv but there is a 30 day demo version available) or the GNU debugger. The last one is free.

Write your programm, link it for the ram area, transfer it to the platform and run it.

Best regards,
Edi

Hey thanks EDDI, I owe ya one.
Your suggestion helped me TONNES with understanding what I needed to to do.



Someday I hope to return the favour.

Until next time;

Psyberbob