GPIO interrupt loss

[jimlin]

Hi I set one GPIO interrupt with low-to-high sense, but seems it did not triggle the interrupt when SD run. I want to confirm the SD would make the interrupt loss? If so, how to raise up the GPIO interrupt priority?

Thanks.

[Susheel Nuguru]

SD can delay app interrupt because SD interrupts have higher priority than app interrupts. i do not think that any interrupts are lost.

[jimlin]

Thanks for reply. But, it seems lost in fact, for the GPIO has been set from low to high, but no interrupt triggle, for I added another GPIO toggle in the interrupt service while nothing happened. Any other possible?

[Susheel Nuguru]

The possible reasons are

1. the gpio is not configured correctly to trigger an interrupt. But this reason will become invalid if you have seen interrupts sometimes.

2. you code has a state machine in your code that is disabling the interrupt.

3)ARM cortex will latch the interrupt, but if the interrupt happens two times before its ISR starts then the latter interrupt will be lost as it will be set to pending bit in NVIC only once. Yes in this case we can look at it as a loss of interrupt as the interrupt was fired too frequently and did not consider that the softdevice could delay interrupts.