| ??? 04/21/07 08:39 Read: times Msg Score: -1 -1 Answer is Wrong |
#137691 - ISR Responding to: ???'s previous message |
Yusuke Oshiro said:
hello experts,
I am new to 8051 and I have a quick question on interrupts that is not covered in the manual / data sheet (as far as I read it). When an interrupt signal (ex1) is received, I want to disable further events from ex1 completely until the ISR is finished. In other words, if another event was received on that port during its ISR, I want to ignore it. I tried to do this by disabling it by simple: CLR EX1 But this doesnt really do. It runs the ISR again as soon as the first ISR is finished. I tried clearing the flag, IE1, on the exit of the ISR to see if this would work, but this again did not work. I am not sure if this the simulator's fault or mine. Any advice / comment will be much appreciated. Cheers, Yusuke Yusuke Oshiro said:
hello experts,
I am new to 8051 and I have a quick question on interrupts that is not covered in the manual / data sheet (as far as I read it). When an interrupt signal (ex1) is received, I want to disable further events from ex1 completely until the ISR is finished. In other words, if another event was received on that port during its ISR, I want to ignore it. I tried to do this by disabling it by simple: CLR EX1 But this doesnt really do. It runs the ISR again as soon as the first ISR is finished. I tried clearing the flag, IE1, on the exit of the ISR to see if this would work, but this again did not work. I am not sure if this the simulator's fault or mine. Any advice / comment will be much appreciated. Cheers, Yusuke Inside any ISR the all the interrepts are automatically cleared but it is internally latched after RETI instruction only it will process. Cheers, Sp.Ganesh |
| Topic | Author | Date |
| Quick question on interrupts | 01/01/70 00:00 | |
| What simulator? | 01/01/70 00:00 | |
| Level driven? | 01/01/70 00:00 | |
| level/edge is irrelevant in this case | 01/01/70 00:00 | |
It's possible | 01/01/70 00:00 | |
| ISR | 01/01/70 00:00 | |
| Not quite | 01/01/70 00:00 |