| ??? 09/26/07 22:24 Read: times |
#145015 - it's good sometimes to violate the rules Responding to: ???'s previous message |
Matthias Arndt said:
Esp. the "keep it short and only set a flag" rule should recieve double attention. I have seen people doing everything in the interrupts and stoping all work because they couldn't debug it anymore... The "rules" in the FAQ are not dogma. In programming, business and love, everything is allowed. I do have a relatively big '51 application, where everything happens in two nested interrupts. The point here is, that what is processed in the interrupts, has to be processed within a tight time budget anyway (e.g. respond to a query via a network, which is idle (read, wasting precious communication time) until the mcu won't respond), so there is no reason to abandon the interrupt, and abort hastily what was been currently processed in main, in order to get the interrupt-produced data processed fast enough... But, of course, this is not the typical picture. Exemptions can be found from each and every line in that FAQ; but by the time one knows how to handle those exceptions one needs no FAQs... So, the FAQ is aimed at the newbies and those are better off following the "rules". Btw., the fact that some programs are harder to debug is IMHO not related to interrupts. It's more about style etc. Matthias Arndt said:
PS: As I use the same technique in my own diploma thesis, is there am official term for those flags? They are not exactly semaphores but somehow a "schedule flag" which schedules a task to be run asap in the main loop. Dunno. Signals, perhaps? JW |
| Topic | Author | Date |
| New FAQ III. | 01/01/70 00:00 | |
| Similarly for 'C' | 01/01/70 00:00 | |
| floating point | 01/01/70 00:00 | |
| "fixed point" FAQ by Erik Malund | 01/01/70 00:00 | |
| corrected FAQ | 01/01/70 00:00 | |
| on 3V3 and 5V | 01/01/70 00:00 | |
| when a RC "debouncing" circuit goes wrong | 01/01/70 00:00 | |
| basic interrupt hints | 01/01/70 00:00 | |
| the C hater | 01/01/70 00:00 | |
| better? | 01/01/70 00:00 | |
| very condensed but clear | 01/01/70 00:00 | |
| it's good sometimes to violate the rules | 01/01/70 00:00 | |
| Rule breaking | 01/01/70 00:00 | |
| The idea of keeping the ISR routine short... | 01/01/70 00:00 | |
| epanded | 01/01/70 00:00 | |
Exactly | 01/01/70 00:00 | |
| flags | 01/01/70 00:00 |