Interesting - every document I've ever seen shows pin 2 as RxD and pin 3 as TxD on a 9-pin D.
J
Jasen Betts
your PC will be looking for RS232 logic levels on the serial port, is that what the receiver produces?
Bye. Jasen
G
gcd
Hi, a few things to look at: ( you using an lpc development board like an lpc-mt-2106? - some of the points below assume you are)
1) use lpc sample code that uses 232 to enusre it's not your code at fault
2) make sure your terminal program isnt using any handshaking, ie xon-xoff or hardware.
3) if you have an oscilloscope use it to see if data really is coming out of the lpc
4) if no o-scope, drop the baud rate as low as possible and use an led ( and a resistor if needed) to see if you can observe data being tx'd ( if low enough could probably use a mulitmeter to see the data too)
5) pin outs d9 d25 txd 3 2 rxd 2 3
if the lpc is a dte then connect lpc pc txd to rxd
if its a dce then connect ( pretty sure the lpc is NOT dce) lpc pc rxd to rxd
6) if the lpc was working and now isn't (which appear to be the issue - from your post i believe it was hooked up to a transmitter at one point and working) then try the following
7)check the voltage test points on the lpc, the 3.3 and 1.8v in particular.
8) if they're ok, then check the data going into the max232 (with the oscilloscope) to see if it's toggling correctly, may be a dead max232?
9) if the volts are ok and the data into the 232 isn't toggling then the arm is most likley cactus, try some sample code that runs the buzzer or other bits n pieces on the lpc
good luck Greg
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