@juande I'm planning to monitor a Solar PV plant.
I would like to monitor it remotely through MQTT so I need to connect to an MQTT server. It is more than 10m away within a dedicated room

Thanks again!

@mistera I tried but could not determine which chip. There are 2 five-pin, one 3.3v reg and the other the battery charge controller.
Try poking around their GitHub here:
https://github.com/Xinyuan-LilyGO/T-Display-S3

https://github.com/Xinyuan-LilyGO/T-Display-S3/tree/main/schematic

https://github.com/Xinyuan-LilyGO/T-Display-S3/blob/main/image/T-DISPLAY-S3.jpg

@jims123
I'm using the Arduino framework, but I initialize ESP-NOW using the IDF function. I include in the project library:
#include <esp_now.h>
#include <esp_wifi.h>

I initialize the WiFi interface like this:
wifi_init();
if (esp_now_init() != ESP_OK) {
Serial.println("Error initializing ESP-NOW");
return;
}

static void wifi_init()
{
ESP_ERROR_CHECK(esp_netif_init());
wifi_init_config_t cfg = WIFI_INIT_CONFIG_DEFAULT();
ESP_ERROR_CHECK(esp_wifi_init(&cfg));
ESP_ERROR_CHECK(esp_wifi_set_mode(WIFI_MODE_STA));
ESP_ERROR_CHECK(esp_wifi_set_protocol( WIFI_IF_STA, WIFI_PROTOCOL_LR ));
ESP_ERROR_CHECK(esp_wifi_set_storage(WIFI_STORAGE_RAM));
ESP_ERROR_CHECK(esp_wifi_set_ps(WIFI_PS_NONE));
ESP_ERROR_CHECK(esp_wifi_start());
int8_t defaultWiFiPower;
ESP_ERROR_CHECK(esp_wifi_get_max_tx_power(&defaultWiFiPower));
Serial.printf("Default power: %d\r\n",defaultWiFiPower);
ESP_ERROR_CHECK(esp_wifi_set_max_tx_power(MAX_WIFI_POWER));
ESP_ERROR_CHECK(esp_wifi_set_country(&country));
}

I get a range on the built-in antennas of about 300m with the visibility of the antennas (no obstacles)

@teastain2 Thank you Terry,

I'll give the instructions a go and see if I make it to work the way I want.

Hi.. I had the same problem.. I flashed the T-Display S3 using a Win10 and the espressif flash download tool (with Thonny always display the invalid header you said). The first issue (in the espressif tool) is to check the location of the firmware file and the memory location are in green. Second I had to flash the T-Display S3 in safe mode (Win10), because at half of the load it disconnected the device. Third put the TDisplay S3 in download mode pressing at the same time the reset and boot buttons, then release first the reset button, next the boot button, finally begin the flash. After that everything was OK. I followed the instructions of this video.. it is in spanish.. but you can switch the subtitles on. https://www.youtube.com/watch?v=bxXz-tmNuWU&t=624s

@sq4cvh I have the same issue and same high current consumption.
I thought I was wrong but I see I'm not the only one....

@teastain2 ... OMG ... I got it running ... and I am almost to embarrsed to tell the reason ... obviously the breadboard I was using for the T-Display was broken and did not have contact for pin 13 😞 Changing the breadboard solved the problem, Ethernet is now working correctly!

@gwer this site is the community site, answered most by other users!

You should raise an “Issue” on the github site.

Hi! I used this code, just now to read the battery voltage from GPIO4.
Do not to declare Input as INPUT mode

top of the sketch:
#define analogPin 4 //the built in battery voltage test point
float val = 1.23; //a test number to check if I'm getting a real value

in "setup"
Serial.begin(115200); // be sure to set USB CDC On Boot: "Enabled"

The entire test loop:
void loop() {
val = analogRead(analogPin); // read the input pin
Serial.println(val/1000); // testing value
delay(1000);
}

That's it...I'm getting 2.94VDC.
The ESP32 has terrible ADC capabilities, so this is it!

I also have a LilyGO T-Display S3 support page on GitHub here:
https://github.com/teastainGit/LilyGO-T-display-S3-setup-and-examples
lots of goodies
-Terry

Nobody wants for the device to wake up from sleep every time it is connected to a charger by USB cable... Nobody wants to take efforts to put it back into sleep by pressing the button afterwards...