| ??? 12/19/07 03:12 Read: times |
#148485 - remove 2k2 resistor Responding to: ???'s previous message |
I am using Atmel 89C51RD2 (not phillips), so I don't know for sure if this will help you or not.
Try connecting psen directly to jumper that connects to GND (no resistor) In one schematic it showed a 22K resistor from psen to GND. When I tried this it never worked. As soon as I removed the resistor, it works perfectly every time provided everything else is done correctly. I use FLIP for atmel. I found that there are problems going into boot mode if it is not done 100% correctly every time. PSEN must be low before power up. IF I switch PSEN low after power up it never works. Did you try a slower baud rate in the terminal testing the "U"? This MAY/MAY NOT help you, but I thought I'd share my ideas. Good Luck |
| Topic | Author | Date |
| Problem with ISP prog of 89c51rd2 with flashmagic | 01/01/70 00:00 | |
| check XTAL (ALE) and RESET | 01/01/70 00:00 | |
| Problem with ISP prog of 89c51rd2 with flashmagic | 01/01/70 00:00 | |
| this is strange | 01/01/70 00:00 | |
| remove 2k2 resistor | 01/01/70 00:00 | |
| tried grounding PSEN | 01/01/70 00:00 | |
| Check ALE ,also 89c51rd1 or 89v51rd2 | 01/01/70 00:00 | |
| WRONG! | 01/01/70 00:00 | |
You are Right | 01/01/70 00:00 | |
| have you read this? | 01/01/70 00:00 | |
| 89C51RD2?? | 01/01/70 00:00 |