| ??? 04/15/07 18:07 Read: times |
#137296 - ok Responding to: ???'s previous message |
doesn't RET pop the last two values off of the stack to form the new program coulter address?
I know I may be ridiculous with a few ajmp's but I'm just pointing out that it is important to terminate your code when it reaches the end. Here is a quote about RET from: http://www.win.tue.nl/~aeb/comp...html#51ret RET is used to return from a subroutine previously called by LCALL or ACALL. Program execution continues at the address that is calculated by popping the topmost 2 bytes off the stack. The most-significant-byte is popped off the stack first, followed by the least-significant-byte. which means that R7 and R6 form the address. According to the quote, the Program counter will equal address R7:R6 if the stack pointer is at 7h and RET is executed before a call. |
| Topic | Author | Date |
| RxD to LCD problems | 01/01/70 00:00 | |
| Serial ISR | 01/01/70 00:00 | |
| work needed. | 01/01/70 00:00 | |
| you need to control flow | 01/01/70 00:00 | |
| confused | 01/01/70 00:00 | |
| this is what I mean | 01/01/70 00:00 | |
| OK | 01/01/70 00:00 | |
| yes | 01/01/70 00:00 | |
| Non-useful Serial ISR | 01/01/70 00:00 | |
| AND it's stuck | 01/01/70 00:00 | |
| thanks | 01/01/70 00:00 | |
| I was going for optimization. | 01/01/70 00:00 | |
| It's functioning | 01/01/70 00:00 | |
| now stay consistent | 01/01/70 00:00 | |
| Terminating code? | 01/01/70 00:00 | |
| . | 01/01/70 00:00 | |
| correct terminology | 01/01/70 00:00 | |
| Missing the point | 01/01/70 00:00 | |
| i get it now | 01/01/70 00:00 | |
| Most, but not all | 01/01/70 00:00 | |
| why on earth | 01/01/70 00:00 | |
| if it\'s almost correct, it\'s still wrong :-) | 01/01/70 00:00 | |
| ok | 01/01/70 00:00 | |
| Not R6 and R7 | 01/01/70 00:00 | |
| well it happend again | 01/01/70 00:00 | |
| Q.E.D. | 01/01/70 00:00 | |
| One further comment is needed | 01/01/70 00:00 | |
| Hey | 01/01/70 00:00 | |
| Dangerous recommendation | 01/01/70 00:00 | |
| good point | 01/01/70 00:00 | |
they all do | 01/01/70 00:00 | |
| it 'trust' the same as 'experiment'? | 01/01/70 00:00 | |
| more issues | 01/01/70 00:00 | |
| Joe, please read this | 01/01/70 00:00 |