| ??? 04/04/08 15:39 Read: times |
#152962 - decoupling Responding to: ???'s previous message |
Thanks for your interest and ideas Richard.
Having tried a second chip with the same result, and got the comms working with several crystals (15MHz, 3.6864MHz and 11.155MHz) I really think think Dallas are telling the truth in saying that crystal frequency is not that critical to it functioning. If it couldn't oscillate fairly reliably, it wouldn't talk to me so clearly. I'm going to concentrate on your second paragraph, specifically all those decoupling capacitors. I didn't have any at all and stuck some in but with no noticable difference so far. I'll go and check. The other thing is that this is on solderless bread board at present. I've had a AT89C2051 running on one at 10MHz and assumed this wouldn't be a problem. Am I wrong? |
| Topic | Author | Date |
| Take this up with the Maxim/Dallas support guys | 01/01/70 00:00 | |
| Why ? | 01/01/70 00:00 | |
| meaty PSU | 01/01/70 00:00 | |
| Mke sure you've got the right software | 01/01/70 00:00 | |
| Dallas MTK | 01/01/70 00:00 | |
| You've got to use exactly the parts they recommend | 01/01/70 00:00 | |
| no scope | 01/01/70 00:00 | |
| I'm not sure this is a deal-breaker ... | 01/01/70 00:00 | |
| same with DS89C420 | 01/01/70 00:00 | |
| decoupling | 01/01/70 00:00 | |
| I have no confidence at all in "breadboards" | 01/01/70 00:00 | |
| stripboard circuit works! | 01/01/70 00:00 | |
| about that bootloader ... | 01/01/70 00:00 | |
| that will not help | 01/01/70 00:00 | |
about those decoupling capacitors | 01/01/70 00:00 | |
| In case you're curious ... | 01/01/70 00:00 | |
| my DS89C450 experience was... | 01/01/70 00:00 | |
| What did you do? | 01/01/70 00:00 | |
| 8052.com SBC | 01/01/70 00:00 | |
| How considerate! | 01/01/70 00:00 | |
| progress ? | 01/01/70 00:00 | |
| programming circuit variations ... FIY | 01/01/70 00:00 | |
| DS89C430 boot loader | 01/01/70 00:00 |