Hi,
I'm having some trouble working with the usb-host controller of an AT91SAM9261 mcu. The CPU stops executing my code if I try to read from the usb-host (address 0x500000). When the mcu crashes it doesn't seem to be jumping to any of the exception-handlers and if I try using the debugger I get an error message that the debugger is "unable to halt the cpu", and then the Debug-message-window is flooded with error messages.
It seem to be related to the RL-RTX library since it seem to work better (it still crashes in certain cases) if I comment out the os_sys_init()-function and don't start the threads.
Does the RL-RTX-lib protect some memory areas or maybe overrides an exception vector or something that might cause this behavior?
I would appreciate any help or suggestions.
Best Regards /Ake Forslund
Ake, Are you using some exotic hardware? something? I had a quick look at the user manual, it does not seem as if you are doing something wrong.
The hardware isn't very exotic, and further testing has shown that there is problem with the initiation of the clocks for the host-controller (When reading the status registers none of the USB-host related clocks are reported active). I'm doing something wrong or maybe not setting a register that I should be setting. I have contacted the support at Atmel and they has sent me contact information for a person that has worked with the same hardware as I am working with now, hopefully he has some insight into this problem and can tell me what I'm doing wrong.
Thank you for your help.