PSoC中断嵌套问题

只看该作者 · 2012-2-18 21:49

一般来说
当高优先级中断正在执行时，低优先级的中断是不响应的

请问，PSoC是不是也一样啊？

只看该作者 · 2012-2-18 21:49

只看该作者 · 2012-2-18 21:58

不同.
只要进入中断,就会自动关闭全局中断允许,不再响应任何中断.直到reti指令自动允许全局中断.
你如果要中断嵌套,需要手动操作允许全局中断.

只看该作者 · 2012-2-18 23:04

我查了官方网站，相同的
Question:
Why do I have to re-enable global interrupts?

Response:
Global nterrupts are disabled in Interrupt Service Routines (ISRs) by default. Re-enabling the global interrupts inside an ISR allows the next pending interrupt to be serviced while inside the ISR that enabled global interrupts. If the pending interrupt is lower priority than the one that enabled global interrupts, it will still be serviced.

Note: If you enable global interrupts inside an ISR that posts interrupts faster than they can be serviced, you may overflow your stack by constantly entering an ISR without exiting it.