physical DMX-out on ESP32-C3 (found possible fix)

[5t0n3r1pp3r]

What happened?

When compiling any version of wled from source(vscode Dev Container)

The DMX pin does not allocate and flickers an led but no DMX is sent reliably. No Light turns on from DMX

I tested the circuit and confirmed the rs485 chip works fine on nodeMCU.

To Reproduce Bug

Compile any 0.15 WLED with DMX on for ESP32-C3-Mini-1 and connect a MAX485 circuit to pin 2.

Expected Behavior

The board should control and send proper DMX on the selected PIN

Install Method

Self-Compiled

What version of WLED?

WLED 0.15.0-b6

Which microcontroller/board are you seeing the problem on?

ESP32-C3

Relevant log/trace output

No response

Anything else?

No response

Code of Conduct

• I agree to follow this project's Code of Conduct

[5t0n3r1pp3r]

Found a solution
After more testing it seems like the pin is being taken over by another process. If i change the pin the odd blink follows it and i cannot get the pin to output correctly
after further testing from adding explicit pin selections in:
ESPDMX.cpp

// Initialize Serial1 with the specified TX pin (2) and no RX
  Serial1.begin(DMXSPEED, DMXFORMAT, -1, sendPin);

This made the DMX start working. I can still see the led flash but the dmx is working on C3- Mini.

Should this line be changed if someone wants to use a different pin?

#ifdef WLED_ENABLE_DMX //reserve GPIO2 as hardcoded DMX pin
  PinManager::allocatePin(2, true, PinOwner::DMX);
#endif

this is found in wled.ccp line 416

[softhack007]

@5t0n3r1pp3r not sure what you're doing .... ESPDMX.cpp is only for 8266. Whatever you change there won't affect your -C3 board.

WLED/wled00/src/dependencies/dmx/ESPDMX.cpp

Line 14 in 1ff667b

#ifdef ESP8266

For esp32 boards, we use the sparkFun DMX driver:

• ESPDmx replaced with SparkFunDMX #2613

Unfortunately the sparkFun driver needs serial2 which is not availeable on -C3 or -S2.

WLED/wled00/src/dependencies/dmx/SparkFunDMX.cpp

Lines 44 to 54 in 1ff667b

	// Some new MCUs (-S2, -C3) don't have HardwareSerial(2)
	#if ESP_IDF_VERSION >= ESP_IDF_VERSION_VAL(4, 2, 0)
	#if SOC_UART_NUM < 3
	#error DMX output is not possible on your MCU, as it does not have HardwareSerial(2)
	#endif
	#endif
	static HardwareSerial DMXSerial(2);
	/* Interrupt Timer for DMX Receive */
	#if !defined(DMX_SEND_ONLY)

Compile any 0.15 WLED with DMX on for ESP32-C3-Mini-1 and connect a MAX485 circuit to pin 2.
The board should control and send proper DMX on the selected PIN

As consequence of what I explained, currently you can't have DMX serial output from WLED on the -C3 board, sorry. Same for -S2. However -S3 mini or -S3 zero might work, if you are looking for a small board.