| ??? 09/16/14 17:46 Read: times |
#190350 - PSEN outputting freq/code does not run |
I am using AT89C51, & xtal freq = 15Mhz.
1. I had checked ALE pin with CRO, it outputs: 15/5 = 2.5Mhz. 2. EA pin is +5V 3. Strange problem: PSEN pin is also outputting freq same as 2.5Mhz. So my code does not run. I had checked for some shorting between two pins but found none. Changed several micro but same problem. Should I pull-up PSEN to +5V with 10K |
| Topic | Author | Date |
| PSEN outputting freq/code does not run | 01/01/70 00:00 | |
| check EA and Pgm | 01/01/70 00:00 | |
| Done checking already | 01/01/70 00:00 | |
| dollars to doughnots I bet | 01/01/70 00:00 | |
| any other reason/remedy | 01/01/70 00:00 | |
| Reset circuit | 01/01/70 00:00 | |
Have you read the datasheet? | 01/01/70 00:00 |