| ??? 03/03/09 08:13 Read: times |
#163015 - What is your XTAL frequency ? Responding to: ???'s previous message |
There is a baud rate calculator on the Keil site I believe.
An 11.059MHz XTAL (with SMOD = 0) should give you a correct 9600 baud. 12MHz will not. The reason that people use a 'U' 0x55 character is because it gives a nice 0101010... picture on an oscilloscope. If you are really receiving a '=' 0x3D character, this is 00111101 which is a strange bit pattern. If you were to use a Terminal that can display HEX characters, I suspect that you have actually received a special char from the ( 0x80 .. 0xFF) range. David. |
| Topic | Author | Date |
| serial comm problem | 01/01/70 00:00 | |
| what about TI? | 01/01/70 00:00 | |
| thank you | 01/01/70 00:00 | |
| Be better... | 01/01/70 00:00 | |
| no luck | 01/01/70 00:00 | |
| Settings | 01/01/70 00:00 | |
| What is your XTAL frequency ? | 01/01/70 00:00 | |
| parity and XTAL | 01/01/70 00:00 | |
| Eh ? | 01/01/70 00:00 | |
| one or the other | 01/01/70 00:00 | |
| my mistake | 01/01/70 00:00 | |
| scope pictures | 01/01/70 00:00 | |
| whatizit? | 01/01/70 00:00 | |
| where I measured it... | 01/01/70 00:00 | |
| waveforms look OK | 01/01/70 00:00 | |
| question | 01/01/70 00:00 | |
| LSBit comes first after startbit | 01/01/70 00:00 | |
| cable | 01/01/70 00:00 | |
| isolation and ESD protection | 01/01/70 00:00 | |
I have blown very few, if any, MAX232's | 01/01/70 00:00 | |
| Your scope trace looks normal | 01/01/70 00:00 | |
| more pics | 01/01/70 00:00 | |
| show picture at PC side | 01/01/70 00:00 |