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Author Topic: ascii through serial/uart not working  (Read 2965 times)

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Offline AdminTopic starter

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ascii through serial/uart not working
« on: April 06, 2008, 02:16:46 PM »
I'm having problems transmitting ascii characters.

I've tried 2 different microcontrollers (AVR and Blackfin), 3 different types of transceivers (rs232, bluetooth, IR), several baud rates (9600, 19200, 38400), and three different serial receive programs (java, hyperterminal, teraterm).

I don't know why it isn't working, but I suspect it has something to do with Windows XP or perhaps my USB drivers.

I know for sure ascii is being transmitted because all the LED's light up during transmit, and regular char and int values transmit fine - but my PC just refuses to accept ascii!

I also noticed that the cursor in both hyperterminal and teraterm freeze whenever ascii is being received, but not when it isn't.

Offline dunk

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Re: ascii through serial/uart not working
« Reply #1 on: April 06, 2008, 04:14:01 PM »
Quote
I don't know why it isn't working, but I suspect it has something to do with Windows XP or perhaps my USB drivers.
you can easily test this with a hard loop on your PCs serial port. (or USB dongle in this case.)
just connect TX and RX on your serial port together (that's pins 2 and 3). make sure hardware flow control is switched off.
now when you type in hyperterminal you should get the same characters echoed on the screen.
if that works then you can rule out XP or USB drivers being the problem.

the only other thing i can suggest is start with the lowest baud rate you can at both ends.


good luck!

dunk.

Offline szhang

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Re: ascii through serial/uart not working
« Reply #2 on: April 06, 2008, 04:17:12 PM »
could it be that your settings in hyperterminal are bad?  Have you checked the handshaking/flow control options?

Offline benji

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Re: ascii through serial/uart not working
« Reply #3 on: April 19, 2008, 07:54:51 AM »
i did the same using an atmega32 connectedd to serial port using max232 ,and yea over windows xp, it works fine,
i did use hyper terminal and it works fine,, anyways i found some better terminal
,,check

braypp.googlepages.com/terminal
good ol' BeNNy

 


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