| ??? 06/03/10 21:44 Read: times |
#176363 - Interrupt Hardware checked on SETB EA? |
According to the 8051 documentation, the interrupt hardware checks for new interrupts on the RETI instruction. It also reacts to specific interrupt events that are not masked (i.e. enabled). But, I can't seem to find any documentation describing what the hardware does when the EA bit is set, meaning directly after the instruction "SETB EA".
Through some experimentation with a SiLabs C8051F340 and the USB debugger, I was able to disable EA, manually set an interrupt flag for timer0, and when EA was re-enabled, the MCU serviced the timer0 ISR. Is this standard 8051 behavior or most likely MCU specific? Thanks, --David |
| Topic | Author | Date |
| Interrupt Hardware checked on SETB EA? | 01/01/70 00:00 | |
| Yes... | 01/01/70 00:00 | |
| the way to see it | 01/01/70 00:00 | |
| so exactly when does the hardware check the interrupt regs | 01/01/70 00:00 | |
| VERY derivative dependent | 01/01/70 00:00 | |
| Datasheet should tell you | 01/01/70 00:00 | |
| ports? machine cycle? | 01/01/70 00:00 | |
Still the datasheet will say. | 01/01/70 00:00 |