Use ESPHome + LVGL instead of Nextion display

[nagyrobi]

TL;DR:
https://github.com/nagyrobi/esp32evse_esphome-lvgl

Here's my plan to use ESPHome + LVGL instead of Nextion display:

ESPHome is adding support for the LVGL graphics library.
Several screens are supported but for this project a WT32-SC01 Plus or Guition JC3248w535 would be most suitable because:

• has a pretty nice case that can be mounted on a box which has esp32-evse inside
• has resolution of 480*320
• has capacitive touch screen
• it runs an ESP32-S3
• has quite some free GPIOs
• A LOT less expensive than Nextion

Running ESPHome on it has the following advantages:

• any useful graphical UI can be rendered via LVGL, with fully open source resources (no proprietary editor needed)
• multiple UARTs can be configured (eg one talking to esp32-evse, other talking to smart meter etc)
• can connect to Home Assistant via native API (or MQTT to other systems), can expose any register as a sensor or control to HA
• can use free GPIOs or the display for anything else
• has Bluetooth and with it you could pair with your car and implement additional related features (eg open charging flap automatically, poll battery status, temperature; garage door control etc, which wouldn't have to interfere with EVSE board at all)

With this it becomes possible not only to have a fully customizable UI, but also:

• 1-click integration with Home Assistant, making possible any notifications or remote access through it
• make own Dynamic Load Management through HA or other ESPHome components (eg use data from other meters in various ways; freely implement DLM logic either in HA or in ESPHome)
• implement any custom authorization like RFiD readers etc

As far as I see the ModBUS feature set is wider that Nextion's so it's already possible to implement more functionality with this kind of display that with Nextion out of the box.

As soon as I get my esp32s2-evse-d-a up and running, will start on this and publish the YAML.

[dzurikmiroslav]

Yes, Nextion is quite outdated and their designer is from the Windows XP era :-) This device with LVGL look good 👍

With a Modbus API, the display must periodically pooling registers ​​from the EVSE. Probably in small time interval, which can be reflected in the performance.

Nextion API is designed to you subscribe to value, and EVSE send you once immediately and next time, when its changed value. I don't know if this data format would be suitable for LVGL, but it is not a problem to implement all other values like Modbus API.

Also you can use Netion API thorught RS485 serial, the same also applies to Modbus API, it can also be used via UART serial.

[nagyrobi]

Yes there is command pendAuth and auth https://github.com/dzurikmiroslav/esp32-evse/wiki/Nextion#table-of-commands

[dzurikmiroslav]

I know about these but did you implement them in your Nextion display? Can't test as I don't have one and don't see in your screenshots
From simulator:

[dzurikmiroslav]

Also do you know what's the Nextion variable name for Charging time? Only the limit is documented

It is chTime I forgot to mention in wiki doc, added...

[nagyrobi]

Published: https://github.com/nagyrobi/esp32-evse_esphome-lvgl

[nagyrobi]

Updated

[Radwan-Alalili]

Is it okay if I use other HMI instead of using Nextion for example CrowPanel touch screen, does the program work fine or there will be some issues

[dzurikmiroslav]

Hi, Sorry, but I'm too busy to solve individual tasks. If you need advice, please post it on the GitHub discussion. Then others who are solving a similar problem will find a solution.

[Y00c]

Hi, Sorry, but I'm too busy to solve individual tasks. If you need advice, please post it on the GitHub discussion. Then others who are solving a similar problem will find a solution.
Thank you dear

[Y00c]

Hi, Sorry, but I'm too busy to solve individual tasks. If you need advice, please post it on the GitHub discussion. Then others who are solving a similar problem will find a solution.

Could you please help me understand how to do this using Arduino IDE with an LVGL esp 32 display? Is there an example available? I couldn't implement it.

[Y00c]

Hi, Sorry, but I'm too busy to solve individual tasks. If you need advice, please post it on the GitHub discussion. Then others who are solving a similar problem will find a solution.

Could you please help me understand how to do this using Arduino IDE with an LVGL esp 32 display? Is there an example available? I couldn't implement it.

![20250316_233134](https://github.com/user-attachments/assets/48495e5c-420e-48e4-ba29-f

6484cf91e4d)

[Y00c]

Hi, Sorry, but I'm too busy to solve individual tasks. If you need advice, please post it on the GitHub discussion. Then others who are solving a similar problem will find a solution.

[nagyrobi]

I thought of having a more precise description on the user interface for the states. What I know so far is:

• A: EV not connected
• B1: EV connected
• B2: EV connected
• C1: Charging
• C2: Charging
• D1: Charging with ventilation
• D2: Charging with ventilation
• E: Connection error
• F: Error

Could you help me understand better the difference between B1-B2, C1-C2 and D1-D2 respectively?

[nagyrobi]

Found this, but I think it doesn't match exactly your implementation.
And here they list a plethora of other possible intermediate stated, but it's apparently for DC chargers...

[dzurikmiroslav]

B1 - is pre authorization state
B2 - is after authorization state
C1/D1 - EV want charging, but AC contractor not connected (for example paused charging, limit reached)
C2/D2 - EV want charging and AC contractor is on

I find out mistake in my diagram (twice has C state) here is fixed

[nagyrobi]

Interesting, it's good we're talking about this. See my feature request issue for details as it appears to be a little different with my car.

[nagyrobi]

Corrected the textual state display in the ESPHome HMI yaml to:

• A: EV not connected
• B1: EV connected
• B2: EV connected, authorized
• C1: Ready to charge
• C2: Charging
• D1: Ready to charge with ventilation
• D2: Charging with ventilation
• E: Connection error
• F: Error

Hope it's correct.

[nagyrobi]

[nagyrobi]

New version, for ESP32-EVSE v2.0 and up, based on AT commands:
https://github.com/nagyrobi/esp32evse_esphome-lvgl
Relies on ESPHome external component:
https://github.com/nagyrobi/esp32evse-esphome
Works on highter baudrates.

Config examples included for:

• Wireless-Tag/Panlee WT32-SC01 Plus
• Guition JC3248w535
• Guition 4848s040: