interrupt priories, which can seem counter intuitive. See\r
configMAX_SYSCALL_INTERRUPT_PRIORITY on http://www.freertos.org/a00110.html\r
3) Calling an API function from within a critical section or when\r
- the scheduler is suspended.\r
+ the scheduler is suspended, or calling an API function that does\r
+ not end in "FromISR" from an interrupt.\r
4) Using a queue or semaphore before it has been initialised or\r
before the scheduler has been started (are interrupts firing\r
before vTaskStartScheduler() has been called?).\r