| ??? 01/24/05 23:58 Read: times |
#85714 - No Luck! Responding to: ???'s previous message |
Michael:
I removed the switch and its pullup resistor completely, connected the reset pin to my development board and programmed it to reset the other microcontroller for 1 sec, still the microcontroller halts. I monitored the reset pin on a DSO and the signal is 100% clean. POR still works and the display shows some programmed graphics. Erik: I modified my development board to accept the graphics LCD, and reset button works great. So I designed a special board for the GLCD with only 2 chips, the microcontroller and the MAX232, and the GLCD of course, I used the same software on my development board with slight modifications of some port pin locations, the display works at power up and get some garbage when reset button is pressed and processor halts. I removed the MAX232 chip leaving the microcontroller and the GLCD alone I got same results. I thought it might be a software problem, I made a simple program to set a pin hi, same problem occurs when reset button depressed. My 2 boards are home made with good ground planes, the development board is single sided (works) while the display board is double sided (reset doesn't work). I can post pictures of both boards if that helps. Any other suggestions or debugging techniques to try out? Mahmood |
| Topic | Author | Date |
| Strange Reset Problem | 01/01/70 00:00 | |
| Is it RC circuit | 01/01/70 00:00 | |
| No RC | 01/01/70 00:00 | |
| Reset Switch Issue | 01/01/70 00:00 | |
| a possibility | 01/01/70 00:00 | |
| No Luck! | 01/01/70 00:00 | |
| Glitches? | 01/01/70 00:00 | |
| I can guess what may be wrong if... | 01/01/70 00:00 | |
| try this | 01/01/70 00:00 | |
| PCB is the only suspect left! | 01/01/70 00:00 | |
| EMI problem | 01/01/70 00:00 | |
which derivative | 01/01/70 00:00 | |
| Power on reset | 01/01/70 00:00 | |
| Is there reset input? | 01/01/70 00:00 | |
| doesn't matter | 01/01/70 00:00 | |
| But what is the problem? | 01/01/70 00:00 | |
| just fixed similar | 01/01/70 00:00 | |
| sounds like wiring problem | 01/01/70 00:00 | |
| It wouldn't be would it? | 01/01/70 00:00 | |
| But Mahmood said, it's not the LCD! | 01/01/70 00:00 |