DMX read example on SparkFun ESP32-S2 Thing Plus

Development Boards ESP32
1

Has anybody gotten the SparkFun DMX Example 2 Input program to work with a SparkFun ESP32-S2 Thing Plus and the SparkFun DMX Shield?

I changed the enable pin to GPIO 3 to match the development board, the program compiles and loads, showing that it thinks DMX was initialized. And I can see that it is getting DMX to the 33/RX1 pin with my scope. But it never shows that anything was received.

I suspect the problem is that the DMX receiving port isn’t being correctly created. The program does this with the “HardwareSerial dmxSerial(2);” statement. I tried changing it to dmxSerial(1), and replacing “dmxSerial” with “Serial1”, but neither helped.

2

Can you share a photo of the setup/wiring? Are both shields using esp32 ThingPlus?

3

No wiring to show. Just a SparkFun Thing Plus - ESP32-S2 WROOM (WRL-17743) plugged into a SparkFun ESP32 Thing Plus DMX to LED Shield (DEV-15110).

Library is SparkFun DMX Shield Library 2.0.1. Program is the Example 2 - DMX Input from that library, with the only change setting enPin to 3 instead of 21.

As I said, the DMX shield is properly delivering DMX to pin 14 of J4 on the ESP32-S2 Thing Plus (33/RX1).

4

Ok; usually these fellas have wiring/cables…it really helps to post those so the people who are responding/trying to help are not making wiring/soldering assumptions :-/

I do see your original intent was to see if someone had gotten example 2 work, so I’ll hang tight while we await such

5

Or maybe look at the example that SparkFun provided with the library. I expect that the problem is with the statement “HardwareSerial dmxSerial(2);” which seems to be an anacronism from the original ESP32 which had three UARTs.

6

Maybe! Hanging tight for now…it’s been about half a day, smarter people than me lurk and post here’n

I only have 1 DMX shield on-hand so I can’t readily recreate the situation as of now :-/

7

Ok I looked at it. With that in mind I still think example 2 requires 2 MCUs (thing pluses, I believe you have 2) and 2 DMX shields (I believe you have one?) wired as detailed in the example 2 section of the hookup guide SparkFun ESP32 DMX to LED Shield - SparkFun Learn; do you have 2 DMX shields?

8

No. I’m generating the DMX signal with a theater lighting console which I know gives a good DMX signal. And that’s the way I’m going to be using it.

So, just one ESP23-S2 and one DMX shield.

I’m looking at the example that just does a read of the DMX signal and prints out what the value in the first slot is.

9

The problem is with specifying the serial port to use. The examples do that with:
HardwareSerial dmxSerial(2);

That probably worked on the original ESP32, which had three UARTs, but the ESP32-S2 has only two. I tried changing it to dmxSerial(1) but that didn’t seem to work.

How do I specify using Serial1?