I am fairly new to arduino and and making in general but understand C fairly well and have been playing around with some projects.
I am trying to connect a dell projector to this little rs232 shifter board that I got from sparkfun https://www.sparkfun.com/products/449 to see if i can turn the projector off and on and control some of its features from the arduino.
Right now I have it hooked to an arduino mega on Serial3 (pins 14/15) and cant seem to get any messages sent to the projector at all.
Dell was nice enough to provide an rs232 pdf sheet for the projector but I feel like I just might not have something right and am not really sure if its my hook up, my code, or both.
Any help or advice on this would be fantastic!
Can I hook this board directly to the arduino using power and ground and just matching RX/TX to RX/TX or do I need a cap or resistor inline? I am totally unsure of any of that.
Heres a link to the dell rs232 pin layout and command list.
The easiest way to get serial communication on the Adriuo working is to connect the RS232 to a COMM port (or RS232 to USB adapter) on your PC. Then use a terminal program to receive/send data for testing the connections and code.
That board does not do true RS232, it just inverts the logic levels. However this will work on newer PC RS232 COM port but may not work on a true RS232 interface. Google “RS232” and read the Wiki article is learn what RS232 level really are.
This is another reason to start with a terminal program and a COM port on the PC.
does convert to true RS232 levels and should work with your projector.
You can/should also do this the other way around. Connect the projector to an RS232 COM port on your PC. Then us the terminal program to control the projector. This will verify that the you are sending the commands correctly and the project does respond.
You’re right, I need to start at the pc and work my way towards using the arduino. I’ll do some homework on getting that aspect working. I appreciate the feedback and help!