Split RS232 and ESP code

[davidebeatrici]

I have a server that is running right next to the inverter, it would be really nice to be able to connect the serial port directly to it using something like https://gitlab.com/Teuniz/RS-232.

Splitting the code into separate classes would definitely help to implement that, among other advantages.

[leodesigner]

Thanks for suggestion.

I wanted to avoid coupling any other external device (orangepi, raspberrypi).
The inverter is quite noisy in RF spectrum and may cause these devices to work less stable.
Especially with the common ground.

I guess we have a lot of other options to communicate over modbus from linux machine.

[davidebeatrici]

Thank you for the fast reply.

My idea was to put at least one filtering capacitor between inverter and computer, but the devices cannot be fully decoupled. An ESP8266 can be sacrificed in case something goes wrong as it's very cheap, a high-end server on the other hand...

I think I'll design a PCB on EasyEDA.

[davidebeatrici]

I completed both schematic and PCB, here's a preview of the latter:

Pictures

Components

Name	Part	LCSC part
C1, C2	GRM21BR61E226ME44L	C86816
C3, C4	GRM21BR60J476ME15L	C77072
C5	GRM155R71H332KA01D	C85963
C6, C7, C8, C9	GRM155R71C104KA88D	C71629
ESP32	ESP32-C3-WROOM-02U-N4	C2926676
ESP32_BOOT	TSG002A05018A	C2888616
ESP32_UART	PZ254V-11-04P	C492403
L1, L2	DFE252012F-1R0M=P2	C435392
PSU	TPS62180YZFT	C73980
R1, R3	CRCW0402470KFKED	C482181
R2	0402WGF1503TCE	C25755
RS232	R-RJ45R08P-A009	C2902700
RS232_UART	MAX3232IPWR	C113205

The power supply is definitely overkill for our needs, but more stuff can be connected to the board by simply soldering wires to it.

I will make the order on JLCPCB, test the hardware and then publish the resources under an open-source license.

[davidebeatrici]

The PCB(s) have arrived!

Pictures

[davidebeatrici]

Alright, the hardware is working as it should! It took me a while to test as I had to fix a few things. I will publish schematics and PCB soon.

The inverter is quite noisy in RF spectrum and may cause these devices to work less stable.
Especially with the common ground.

You were absolutely right: when powered by the RS232 port, simply connecting the ground from the ESP32's UART header to a CH340 interface causes the computer's USB port to reset continuously... any ideas on how to fix that?