| ??? 07/07/06 13:35 Read: times |
#119812 - The value of Flag is known! Responding to: ???'s previous message |
Jon Ledbetter said:
void externalinterrupt(void) interrupt 0 //invoked on every positive edge
{
if( !flag ) {
TR0 = 1; //enable timer0
flag = !flag; <---- shouldn't this be !flag=flag ??
} No, I don't think so - the '!' operator needs to be on the RHS. However, why bother with an expression at all? At this point in the code, we know that 'flag' (what a useless name for a variable) must be 'false' - so we might just as well assign it to 'true' directly!
if( !flag ) {
// At this point, flag must be false
TR0 = 1; // enable timer0
flag = TRUE; // flag was false; set it true
}
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| Topic | Author | Date |
| frequency of a digital pulse | 01/01/70 00:00 | |
| Variable definitions ? | 01/01/70 00:00 | |
| Please post formatted code | 01/01/70 00:00 | |
| Some points: | 01/01/70 00:00 | |
| misconceptions cleared | 01/01/70 00:00 | |
| inappropiate response | 01/01/70 00:00 | |
| the entire problem again | 01/01/70 00:00 | |
| flag=!flag ? | 01/01/70 00:00 | |
| The value of Flag is known! | 01/01/70 00:00 | |
| I see, but I don't C | 01/01/70 00:00 | |
| It's illogical, Captain... | 01/01/70 00:00 | |
It is worse than that | 01/01/70 00:00 | |
| nope | 01/01/70 00:00 | |
| Please post formatted code!! | 01/01/70 00:00 | |
| he did follow the instructions | 01/01/70 00:00 | |
| Oh no he didn't! | 01/01/70 00:00 | |
| Argument | 01/01/70 00:00 | |
| well, I saw the indentions and - shame | 01/01/70 00:00 | |
| formatted code................. | 01/01/70 00:00 | |
| thus therefore undefined | 01/01/70 00:00 | |
| Formatted, but not the same code! | 01/01/70 00:00 | |
| 2 problems off the top | 01/01/70 00:00 | |
| a blatant understatement | 01/01/70 00:00 | |
| Implicit casting mess. | 01/01/70 00:00 | |
| commentless code is worthless | 01/01/70 00:00 |