@RebelJD

Posted by: @rebeljd

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I'm attempting to interface a Nextion Display  (Enhanced version) with an ESP32, but can't seem to make it work.  Has anyone been able to make this work?

Jim

Jim,

Yes, I completed a project in the spring that used three NEXTION displays.  Here is the link to the project and code  https://forum.dronebotworkshop.com/show-tell/rabbit-shack-chicken-coop-automation-project/

I used the Easy Nextion library, but I needed to change one line of code in the library to get the serial port to work.  LMK if you have any questions.

Mike

Mike, thanks for the quick reply.  You did a nice job of documenting the project, something I always try to do also.  It makes trouble shooting in the future much easier.  I've not read thru everything yet, but I had a few questions if you don't mind.  In looking at the schematic it does not appear you incorporated any level shifting of the 3.3v of the ESP32 to the 5v TTL of the Nextion, does that work ok?

Also, it appears that 3.3v from the ESP32 is tied to pin 3 of the connector in the lower right which is also tied to the 5v that goes to the Nextion.  The resolution the drawing is not great so maybe I'm not seeing it correctly.

I'm going to take a good look at Easy_Nextion_Library, I've not seen that before.

Thanks again,

Jim

@rebeljd 

Press the "Reply" button and it will add @huckohio to the message.  That way I'll get an email when you respond.

There are two level shifters in the schematic.  The are labeled as "Logic Level Converter" (see attached pic).

I place everything on single row pin headers so I can pull out the chip/board as required.  So you won't see the actual chip/board identifier, just the connector.

The 3.3v from the ESP32 is going to each of the logic level converters for the "low" side power.

LMK if you have any other questions.

Mike

@rebeljd

Posted by: @rebeljd

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Also, it appears that 3.3v from the ESP32 is tied to pin 3 of the connector in the lower right which is also tied to the 5v that goes to the Nextion

Forgot to address the 5V.  The 5V signal line you see is providing 5V to both the logic level converter "high side" and to the nextion display.

@huckohio Got it, thanks.  I thought those were connectors.  Makes sense now that I know they are logic level converters.  What device did you use for converters?  

Sorry to ask all the questions but I really want to use ESP32 on this, not an Arduino.  

@rebeljd 

KeeYees 10pcs 4 Channels IIC I2C Logic Level Converter Bi-Directional Module 3.3V to 5V Shifter for Arduino (Pack of 10)

@rebeljd 

This is the ESP32 I used.

ESP32-S3-DevKitC-1-N8R2 Development Board

@huckohio @rebeljd Wow, that is pretty much the top of the line in esp32s, you may well be able to make your project with a more affordable but also time proven S2 series like the venerable DOIT. They both will work, but newer may mean there are still some bugs. I try to have one of every board so I can compare but that is just me. I will favour the older models unless I need a new feature so I can be relatively sure it is as close to bug free as reasonably possible.

@huckohio @zander

Mike, thanks for all your help, I was able to get the ESP32 and Nextion display to communicate.  I ended up using the EasyNextionLibrary and your work around on using Serial2 on the ESP32.  I'm using an ESP-WROOM-32 Dev Kit and Nextion 3.5" Enhanced.  I haven't written all the code yet but I know enough to move forward now.

I'm going to document the basic set up to hopefully help others get up the learning curve a little quicker than I did.  

Once again the Drone Bot Workshop forum came thru with the needed help.  Awesome.  

I'm going to create a new topic titled "ESP32 to Nextion Lessons Learned.

@rebeljd 

I would make it clear that this LL refers to using the ESP32 with the Easy Nextion Library.  My only issue was getting Serial2 to work.  Once I have that working the rest was easy.