So I'm trying to get a signal thru an M5 Atom Lite with an RS232 base in order to monitor some solar inverters and it was recommended to run an RS232 isolator between the sending and receiving ends of the cable to protect the inverter at the rj45 port. So it goes, M5 Atom with RS232 base to a male DB9, RS232 isolator, then RS232 to RJ45 cable. Signal is sent over Wifi to the Atom Lite, which is supposed to query the inverter and the inverter is suppose to respond back with data like temp, pv power, load, etc.
My problem is, when I send the signal without the isolator I see it on the scope, when I add in the isolator, no signal. Here is how I tested:
Using a RS232 breakout male connector wired just like the attached image where Gnd to breakout 5, Tx to breakout 2, Rx to breakout 3.
According to the RS232 pinout for a male connector, Pin 2 is Rx and Pin 3 is Tx. So Tx on the RS232 base becomes Rx at the male connector, and Rx on the RS232 base becomes Tx. This picture is from someone helping me who wrote the code, but I have mine setup the same way...he said the Rx should become the Tx at the DB9 and Tx become the Rx...I've tried just for testing to reverse the wires (Rx to Rx) (Tx to Tx) and it still doesn't work at the inverter with the isolator...I haven't tried it without the isolator as I don't want to risk damaging the inverter which I'm not sure actually is a risk.
The scope is connected as follows (we included RTS and DTR to see if these needed voltage for some reason to make it work):
CH1 = Male connector Pin 3 (Tx), CH2 = Pin 2 (Rx), CH3 = Pin 7 (RTS), CH4 = Pin 4 (DTR).
So when I run this command to create a docker container (I'm testing with root to avoid any permission issues)...IP below is of the Atom:
docker run --privileged=true --user root -t gonzalomono/wombatt monitor-inverters 192.168.1.166:8232,Q1 --device-type tcp
...the Terminal Window reads this (run from an OrangePi):
2024/06/08 11:35:22.221315 Opening 192.168.1.166:8232...
...I get this at the Atom Tasmota log (confirming the static IP address of the OrangePi):
12:35:21.326 TCP: Got connection from 192.168.1.17 (We'll disregard the inaccuracy of the timestamps for now)
...when that happens...the scope reads the attached image that shows a signal.
then after 5 seconds the Terminal Window reads this:
2024/06/08 11:35:27.271689 error running Q1 on 192.168.1.166:8232: timed out sending Q1
and it cycles...but I press ctl-c to quit.
Then when I try with the same setup but with an added in RS232 isolator, I get image attachment which shows no signal. I've even tried a different isolator, same thing. I'm a little stumped on where to look for the problem. Can someone please help? Thanks.