| Richard Erlacher 01/25/10 16:42 Read: 170 times Denver, Co USA |
#172721 - Try it with a crystal oscillator, rather than a crystal Responding to: Hans Marée's previous message |
It would seem, from your writing, that your "crystal oscillators" are really just crystals. If you drive the X1 (on most 805x-types) input with a crystal oscillator rather than simply tying a crystal between the two Xn pins, and adding the load caps to GND, you'll get better results. I typically use a rather common 33 MHz oscillator, as a result of which code that sets the MCU's UART to operate at 19.2 kbps, will operate at 57.6 kbps. You can probably find a 33 MHz oscillator on some old PC motherboard back in someone's closet.
RE |
| Topic | Author | Date |
| execution speed and crystal frequency | Hans Marée | 01/25/10 10:29 |
| my guess is ... | Erik Malund | 01/25/10 11:26 |
| overtone | Stefan KAnev | 01/25/10 11:27 |
| As others already mentioned... | Kai Klaas | 01/25/10 13:16 |
| Indeed overtone | Hans Marée | 01/26/10 13:48 |
| Just try the crystal with 15pF + 15pF caps. | David Prentice | 01/26/10 14:26 |
| Try it with a crystal oscillator, rather than a crystal | Richard Erlacher | 01/25/10 16:42 |
| baloney | Erik Malund | 01/25/10 16:51 |
| Baloney #2 | Andy Neil | 01/25/10 18:02 |
| Where is your head wedged, Erik? | Richard Erlacher | 01/25/10 18:38 |
| just correcting invalid info | Erik Malund | 01/25/10 19:00 |
| SO ... What, exactly, is incorrect? | Richard Erlacher | 01/25/10 23:35 |
| already stated | Erik Malund | 01/26/10 07:33 |
| You are showing us how smart you are again, Erik! | Richard Erlacher | 01/26/10 09:28 |
| not my intention, but thanks for the compliment | Erik Malund | 01/26/10 09:46 |
| Richard is right... | Kai Klaas | 01/26/10 10:12 |
| I do not use these and .... | Erik Malund | 01/26/10 10:19 |
| Fact is ... | Richard Erlacher | 01/26/10 18:49 |
| as Kai stated | Erik Malund | 01/26/10 19:19 |
| so ... Erik ... what's your point? | Richard Erlacher | 01/26/10 21:25 |
| I did | Erik Malund | 01/27/10 05:32 |
| Once again, Erik, you've missed the point | Richard Erlacher | 01/27/10 09:58 |
| YOU would sell a suicide candidate a rope | Erik Malund | 01/27/10 11:15 |
come on... | Stefan KAnev | 01/27/10 12:08 |
| come on... | Stefan KAnev | 01/27/10 12:07 |
| Specifying Quartz Crystals | Enrique Viseras-Marin | 01/26/10 06:35 |