STM CircleOS forum / interrupts during Application_Handler "time slice"

adal · 2009-11-10 15:08:18

Hi,

I have a problem.

My application sends commands and waits for answers through USART2.
Although receiving charachters bytes from usart is triggered by interrupt having
*higher priority* than systick I still have to exit the Application Handler through
"return MENU_CONTINUE_COMMAND;" to get usart inputs (and re-enter the handler later keeping the systick frequency).

I don't know much about CircleOs(v3.7) scheduling, but I'm just wondering if interrupt
handling is postponed at after the exit from the Application_Handler even for interrupts
having a priority that is higher than systick...

Adalberto

Francis · 2009-11-13 09:26:12

In 'standard' mode (without considering USB for mass-storage), two interrupts are used:
1. Systick, that calls most of the handlers,
2. Timer2 (higher priority) that is used to access the MEMS with a fixed frequency. The timer2 handler used to manage the I2C communication with the audio device too (version 3.0 to 3.7). Bu tthis call has been moved into the audio handler in 3.8.
If you don't care about fixed values for the MEMS, you can (dynamically, without recompiling CircleOS) disable the Timer2 interrupt. If you still need to keep the MEMS features, you will have to call sometimes the MEMS handler... (that is by default the Timer2 interrupt handler).

# 1 2009-11-10 15:08:18 interrupts during Application_Handler "time slice"

interrupts during Application_Handler "time slice"

# 2 2009-11-13 09:26:12 interrupts during Application_Handler "time slice"

Re: interrupts during Application_Handler "time slice"

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