| ??? 05/23/05 13:53 Read: times |
#93757 - I tried Responding to: ???'s previous message |
I've just tried on a AT89C8252 with 11.0592HMz Xtal (+2x33pF caps) and an el-cheapo digi multimeter.
When running, XTAL1=1.28V, XTAL2=2.28V. When disconnecting the Xtal, XTAL1=1.25V, XTAL2=2.32V. When shorting, XTAL1=XTAL2=2.20V. The little digi is really a crap. So I piced up our old but reliable Fluke, and it reads around 2.15V on XTAL1 and 2.25V on XTAL2 while running. Clearly the noname digi loads the "input side" too much. I would conclude, that measuring 2.2V on the XTAL pins does not prove that oscillator is running. But, on the other hand, I believe that measuring anything way off (especially on XTAL2) most probably means that the oscillator is not running. Jan Waclawek |
| Topic | Author | Date |
| works on simulation but not on hardware | 01/01/70 00:00 | |
| How can the hardware be working.... | 01/01/70 00:00 | |
| Thanks Michael | 01/01/70 00:00 | |
| Voltmeter - Answer is partly wrong! | 01/01/70 00:00 | |
| square wave with high frequency | 01/01/70 00:00 | |
| Invalid Deduction | 01/01/70 00:00 | |
| Bad evolvement! | 01/01/70 00:00 | |
| I tried | 01/01/70 00:00 | |
| Jan you are a powerful understand-er | 01/01/70 00:00 | |
| Measuring frequency with Voltmeter! | 01/01/70 00:00 | |
| by maens othere that the right one | 01/01/70 00:00 | |
What an idea!! | 01/01/70 00:00 | |
| Today says from yesterday | 01/01/70 00:00 | |
| Oh,as the same of my baby | 01/01/70 00:00 | |
| Sorry Mehdi, you're misguided. | 01/01/70 00:00 | |
| Philips App Note - Crystal Oscillators | 01/01/70 00:00 | |
| I am talking about a small module only | 01/01/70 00:00 | |
| Not a good way to get help | 01/01/70 00:00 | |
| works on simulator | 01/01/70 00:00 | |
| works on simulator | 01/01/70 00:00 | |
| I do not know | 01/01/70 00:00 | |
| When Simulation & Real-Life Differ | 01/01/70 00:00 |