| ??? 12/09/05 17:12 Read: times |
#104988 - 80c32 Problem with ALE/PSEN/EA |
Hi,
This is my first Post here, I am (nearly) new to the 8051 Controller. My First Project was with ATMEL 89c2051 and worked fine. No I am trying to build a System with erternal ROM/RAM. For that i am using an old 80c32 from TEMIC. My Problem now is: when connecting /EA to GROUND, the Oszillator stops completely after a few moments. I thought that the Quarz may be the reason, an d tryied severel different ones. At last, i simply used an external Oszillator which could not stop working. But now it is even more curious: i switch on the board, ALE and PSEN are pulsing nice but suddenly stop. When resetting the Controller, the same starts all over again. Now i connected EA to Vcc and ALE didnt stop. Another interesting thing is, that when ALE stopped, a few Port pins show nice 50 Hz square-waves although i drive the board from an akku and everywhere are Caps connected between VCC and GND. Sorry for the long and badly written text, but it really makes me crazy. Greetings from Germany Michael |
| Topic | Author | Date |
| 80c32 Problem with ALE/PSEN/EA | 01/01/70 00:00 | |
| Why? you can buy a P89C668 (64k flash/8k | 01/01/70 00:00 | |
| /EA to ground while Running | 01/01/70 00:00 | |
| Why not let him do what he wants? | 01/01/70 00:00 | |
| Nope | 01/01/70 00:00 | |
| well.. | 01/01/70 00:00 | |
| Too wise! | 01/01/70 00:00 | |
| Then be more specific. | 01/01/70 00:00 | |
| Assumptions! | 01/01/70 00:00 | |
| Newness of OP | 01/01/70 00:00 | |
| You are missing the point | 01/01/70 00:00 | |
| Answers to the point | 01/01/70 00:00 | |
| there can be | 01/01/70 00:00 | |
| Of course! | 01/01/70 00:00 | |
| re newbie and 8032 | 01/01/70 00:00 | |
| He doesn't need that ... | 01/01/70 00:00 | |
| how is he going to do the EPROM that hol | 01/01/70 00:00 | |
| That's easy, but it's not the point | 01/01/70 00:00 | |
"Why?" is that "telling him" | 01/01/70 00:00 | |
| powerdown mode | 01/01/70 00:00 | |
| That could be the Problem | 01/01/70 00:00 | |
| empty ROM? | 01/01/70 00:00 | |
| use the lower crystal value | 01/01/70 00:00 |