Serial Issue

Hello all..

I recently got into using arduinos and am working on a project at work with it. We have the code up and running but ran into a strange problem when trying to send serial out of the TX pin.

When we have the Arduino hooked up to the computer with USB and have the serial monitor on, the code is sent fine.. when we unhook the usb and try to send it into the serial port on the computer what we get is random characters. We triple checked the wiring and it is on the right baud speed 9600.

Any thoughts on this would be much appreciated.
Thanks.

Serial ports on computers have voltage levels according to the RS232 standard, that is +- 15V !

This can kill the arduino's serial port (TTL levels).

What you need is a level shifter, e.g. a MAX232.

That makes total sense.
Totally missed that.

Going to order one of these.

Thanks alot.