LOOPBACK TEST RS232 SERIAL

You would also have to separate pins 2 and 3 so that you could enable both the driver and the receiver simultaneously, which you could do on your breadboard by just attaching pin 2 to ground and pin 3 to Vcc. You would have to separate pins 1 and 4 and connect them to separate pins on the MCU. So what can I do with the output from the max485 on the breadboard to test if it is working? I thoguht if I connected the output pins together it would loop back to the pc? I'm confused. PC -> converter/max485 -> max485/breadboard -> output rx/tx connected to each other (pins 1 and 4).

LOOPBACK TEST RS232 SERIAL

So the output Rx/Tx pins from the max485 on the breadboard should be readable serial data right? I have it like this:

My converter has a max485 in it, which is then hooked up to the max485 on my breadboard. Does that mean the converter is possibly broken for the rs485 part? Or is the output from the A and B lines not in a readable format until it passes through a max485?Īre there any other steps I could perform to determine if my coverter is broken or if the max485 is fried? But this doesn't happen with the rs485 A and B lines out of the converter. Interestingly, out of my converter using the rs232 outputs, if I connect the rx/tx together directly without using the max232 I get a positive loopback. Connecting the Rx and Tx pins together on the max232 is how I performed the loopback test, but when I do this with the max485 I get nothing back. Finally I have pins 1 and 4 of the max485 connected together in an attempt to perform a loopback. I then have the A and B lines from the converter going into pins 7 and 6 of the max485. I have vcc and ground from the converter going into pins 8 and 5 of the max485. My setup is I am using the following usb to rs232/rs485 converter: Is it possible to do a loopback test with the max485 like I did with the max232 or am i misunderstanding how the max485 works?

However, I am not able to do either when I switched the max232 out for the max485. I can upload code to the atmega as well as perform a loopback test. I have been able to successfully implement an atmega328p setup on a breadboard with a max232.

Loopback test rs232