RS232 comms problem

Ron Simpson

Hi All

I have a new Propeller set up aka PropStick but on a bread board. I have it working doing I2c comms etc but I cannot get rs232 comms to work.
I am using a 5MHz crystal and setting the clock mode and frequency. To test the connection I am using "Simple debug" connected to hyper terminal
on the PC using the upload max3232 circuit. What appears to be happening is that the baud rate cannot be correctly set. Whatever rate I set the best
I can do is receive corrupted characters.

Any suggestions

Post Edited (Ron Simpson) : 2/5/2008 10:12:55 PM GMT

Leon

No subject!!!

Try sending 'U' continuously and check the output with a scope. You should be able to measure the bit width and chck that it is correct.

Leon

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Post Edited (Leon) : 2/5/2008 10:17:13 PM GMT

Ron Simpson

Thanks Leon


Unfortunately I do not have access to a scope so need to try tracking down the problem more indirectly.

Ron

deSilva

Ron, you must be aware that this works for everyone in the world, so we have to learn what's the difference with you. Give us some more data, please.

Leo asked you to perform some tests. Go on with this. Send th esame character; change the bir rate... when can you se what... Is it always the same? You will sometimes see twice as many characters, then the bit rate is around twice as heigh as needed.

Post the code you use....
Post the circuitry.

There is no need for any MAX232 or similar schnick-schnack. A Propeller PC conection runs fine with a resistor only.

Change the ports to 30, 31 where the USB is. If this doesn't work, it's your program.

Enough ideas??

Ron Simpson

Thanks Problem solved.

Wrong _clkfreq

The obvious can be impossible to see at the end of a long day.
Ron