| ??? 05/10/05 17:10 Modified: 05/10/05 17:11 Read: times |
#93279 - Maybe... Responding to: ???'s previous message |
Christian Kleiber said:
Did you try to look the ALE signal in an oscilloscope? it pulses crystal frequency/6 if i'm correct
I always check it and if ALE pules it means the uC is alive That is not guaranteed to be universally true. If the device is executing from external program space, executing MOVC from external program space, or executing MOVX to/from xdata, that's true. However, if none of those things are happening, it is possible on the AT89C51 that the regular pulsing of ALE could have been disabled in firmware. --Sasha Jevtic |
| Topic | Author | Date |
| crystal problem - 89c51 | 01/01/70 00:00 | |
| ALE | 01/01/70 00:00 | |
| Maybe... | 01/01/70 00:00 | |
| two capacitors or one?? | 01/01/70 00:00 | |
| milli? | 01/01/70 00:00 | |
| read Atmel | 01/01/70 00:00 | |
| Use XTAL2 pin for freq. measurment | 01/01/70 00:00 | |
| Better use 22MHz fundamental + two 27pF | 01/01/70 00:00 | |
| tried for low capacitance | 01/01/70 00:00 | |
| bible time | 01/01/70 00:00 | |
This should help | 01/01/70 00:00 |