Stm32 What is the difference between the interrupt preemption priority and the response priority level

Unlike 51, Stm32 's interrupt classification is more flexible. 51 are interrupted in chronological order of size.

The concept of response priority is more stm32.

Stm32 interrupts are divided into 1. preemption (preemptive) priority. 2. Response priority.

1. preemption priority. Preemption of high-priority interrupts can interrupt a low-priority interrupt.

2. Response priority. Preemption with the same priority and high priority can be performed first.

There may be questions: preemption of the same priority interrupt, high response priority can not interrupt the low-priority interrupt response. Two interrupts must be who first came on the corresponding who, two interrupts cannot come at the same time. What is the use of the response priority?

In fact, the response priority mainly gives a priority queue for the response. Assume that the preemption priority for interrupts is the same. If there are multiple interrupts with the same preemption priority, they will not interrupt each other, but their subsequent queues will be queued according to the priority of the response. That is, in the period when the first interrupt is not completed, the next highest priority of the response is scheduled to the highest wait bit processing.

This provides the possibility of an atomic operation, that is, an operation that cannot be interrupted.

What's the wrong, please point!

Stm32 What is the difference between the interrupt preemption priority and the response priority level