| ??? 12/26/05 10:21 Read: times |
#105956 - Is the CPU really running? Responding to: ???'s previous message |
I had a similar problem with one of my new 89C52 boards.
A very simple program , similar to the one being dicussed here, was running perfectly in simulator, but not on the board. After spending a lot of time, I discovered that track from pin 31 - EA\/Vpp signal to Vcc had a small crack and practically this pin was open. so probably the program was not ruuning from internal program memory. After correcting this mistake, the program started working fine. One easy way of discovering if CPU is running from internal program memory or not is toggle some port pin within a loop and at different points of the path of execution . If the pin toggles as expected, it means program is running along the expected execution path else.. Is this the problem in this case? |
| Topic | Author | Date |
| this code is not working | 01/01/70 00:00 | |
| You solved it! | 01/01/70 00:00 | |
| overreaction | 01/01/70 00:00 | |
| Humility ? | 01/01/70 00:00 | |
| Call it cultural difference... | 01/01/70 00:00 | |
| Sounds familiar | 01/01/70 00:00 | |
| thanks Jan Waclawek | 01/01/70 00:00 | |
| Keil's startup.a51 | 01/01/70 00:00 | |
| hex seems OK | 01/01/70 00:00 | |
| re hex seems OK | 01/01/70 00:00 | |
| And the switch? | 01/01/70 00:00 | |
| and switch | 01/01/70 00:00 | |
| Try a pull-up | 01/01/70 00:00 | |
| switch function | 01/01/70 00:00 | |
| Not at all | 01/01/70 00:00 | |
| reset cap | 01/01/70 00:00 | |
| yeah | 01/01/70 00:00 | |
| It can! | 01/01/70 00:00 | |
| points | 01/01/70 00:00 | |
| Some suggestions | 01/01/70 00:00 | |
| nope | 01/01/70 00:00 | |
| Use LEDs | 01/01/70 00:00 | |
| ok let me follow | 01/01/70 00:00 | |
| That sounds good ! | 01/01/70 00:00 | |
| try this code | 01/01/70 00:00 | |
and what good will that do? | 01/01/70 00:00 | |
| How? | 01/01/70 00:00 | |
| capital | 01/01/70 00:00 | |
| Thanks! | 01/01/70 00:00 | |
| I did the same thing recently | 01/01/70 00:00 | |
| At least... | 01/01/70 00:00 | |
| HORSEFEATHERS | 01/01/70 00:00 | |
| i think yopu didn't got the message | 01/01/70 00:00 | |
| of course it is not | 01/01/70 00:00 | |
| It's easy to fix the code | 01/01/70 00:00 | |
| no, he does not | 01/01/70 00:00 | |
| wrong suggestion | 01/01/70 00:00 | |
| it DOES NOT write to R0 | 01/01/70 00:00 | |
| RE: it DOES NOT write to R0 | 01/01/70 00:00 | |
| why the continued discussion | 01/01/70 00:00 | |
| Time zone | 01/01/70 00:00 | |
| just another guess | 01/01/70 00:00 | |
| She is most likely from India | 01/01/70 00:00 | |
| Irony | 01/01/70 00:00 | |
| Help me | 01/01/70 00:00 | |
| re help me | 01/01/70 00:00 | |
| What happens if? | 01/01/70 00:00 | |
| i will see | 01/01/70 00:00 | |
| "mov @r0,#00h" by "NOP, NOP"? | 01/01/70 00:00 | |
| A good idea | 01/01/70 00:00 | |
| nothing postive | 01/01/70 00:00 | |
| RAM fill ? | 01/01/70 00:00 | |
| re ram fill | 01/01/70 00:00 | |
| Simulator. | 01/01/70 00:00 | |
| Is the CPU really running? | 01/01/70 00:00 | |
| mov p1,r0 | 01/01/70 00:00 | |
| last hope | 01/01/70 00:00 | |
| Tell this first | 01/01/70 00:00 | |
| let me clear | 01/01/70 00:00 | |
| pull ups | 01/01/70 00:00 | |
| re pull ups | 01/01/70 00:00 | |
| a word on pull ups | 01/01/70 00:00 | |
| What to say for that ignorance? | 01/01/70 00:00 |