incrediball wrote on Thursday, June 04, 2009:
Some changes are needed to use FIQ:
1. Create a stack for the FIQ.
2. Set up the FIQ vector. This is often coded as an endless loop or something equally pointless.
3. If interrupt latency is an issue (in my case it was), stop FreeRTOS from disabling the FIQ in portDISABLE_INTERRUPTS, vPortDisableInterruptsFromThumb and vPortEnterCritical.
The FIQ interrupt handler must not interact with FreeRTOS. If it needs to communicate with the rest of the system, it can raise a regular interrupt in software (use AT91F_AIC_Trig).
I wrote about it last year under [url]https://sourceforge.net/forum/message.php?msg_id=4901759[/url]