| ??? 03/06/09 02:41 Read: times |
#163133 - question Responding to: ???'s previous message |
Thank you for the reply. Looking at the 232 bit stream explanation at this website, I'm a little confused about the byte I'm actually seeing from my board. When the signal is positive (according to the above reference), that equates to a 0 and vice versa for a negative signal. Looking at the U scope image I posted yesterday, the stream is 0101010101. If the first bit is the start bit (positive signal), that would mean I'm receiving a 10101010 which I know isn't right because ASCII characters always start with a 0. Is the signal inverted out a MAX232?
As for the cable, it is a new cable so it may very well be bad. I use the serial port itself all the time for PLC programming and have never had an issue reading from or writing to the serial port. I also just tested it with a serial compass into HyperTerminal and all is well. I have a couple more cables around so I'll give that a try. Thanks again, Brian |
| 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 |