Some set of parameters, and already work the two loops without interference.

#include"M5Stack.h"

int mensaje=0;
int mensaje1;
QueueHandle_t queue_1;
void loop_tarea1(void * pvParameters);

void setup(){
M5.begin(); // inicio del M5s
queue_1 = xQueueCreate(1, sizeof(int));
if( queue_1 == 0 )
{
m5.Lcd.setTextSize(2);
m5.Lcd.print("no creada la lista");}
xTaskCreatePinnedToCore(loop_tarea1, "Tarea1",1500, NULL, 1, NULL,0);
}

void loop_tarea1(void * pvParameters)
{
for( ;; ) {
if (xQueueReceive(queue_1, &mensaje1, ( TickType_t ) 10) ) {
m5.Lcd.setTextSize(5);
m5.Lcd.setCursor(150,0);
m5.Lcd.print(mensaje1);}
}
}

void loop()
{ mensaje=0;
if (Serial.available()){
mensaje=Serial.read();
xQueueSendToFront(queue_1, &mensaje, ( TickType_t ) 10); }
delay(10);
}

Some set of parameters, and already work the two loops without interference.

#include"M5Stack.h"

int mensaje=0;
int mensaje1;
QueueHandle_t queue_1;
void loop_tarea1(void * pvParameters);

void setup(){
M5.begin(); // inicio del M5s
queue_1 = xQueueCreate(1, sizeof(int));
if( queue_1 == 0 )
{
m5.Lcd.setTextSize(2);
m5.Lcd.print("no creada la lista");}
xTaskCreatePinnedToCore(loop_tarea1, "Tarea1",1500, NULL, 1, NULL,0);
}

void loop_tarea1(void * pvParameters)
{
for( ;; ) {
if (xQueueReceive(queue_1, &mensaje1, ( TickType_t ) 10) ) {
m5.Lcd.setTextSize(5);
m5.Lcd.setCursor(150,0);
m5.Lcd.print(mensaje1);}
}
}

void loop()
{ mensaje=0;
if (Serial.available()){
mensaje=Serial.read();
xQueueSendToFront(queue_1, &mensaje, ( TickType_t ) 10); }
delay(10);
}

I keep studying how to share data between the two loops, I have located the FreeRtos manuals and they are very complex for my level. I have written this code, but with the same result ,when sending data the M5stack will reboot . I'd appreciate some help.

#include"M5Stack.h"

int mensaje;
int mensaje1;
QueueHandle_t queue_1;
void loop_tarea1(void * pvParameters);

void setup(){
M5.begin(); // inicio del M5s
queue_1 = xQueueCreate(4, sizeof(int));
if( queue_1 == 0 )
{
m5.Lcd.setTextSize(2);
m5.Lcd.print("no creada la lista");}
xTaskCreatePinnedToCore(loop_tarea1, "Tarea1", 500, NULL, 2, NULL,0);
}

void loop_tarea1(void * pvParameters)
{
for( ;; ) {
if (xQueueReceive(queue_1, &mensaje1, portMAX_DELAY) == pdPASS) {
m5.Lcd.setTextSize(5);
m5.Lcd.setCursor(150,0);
m5.Lcd.print(mensaje1);}
}
}

void loop()
{ mensaje=0;
if (Serial.available()){
mensaje=Serial.read();
Serial.print(mensaje);
delay(100);
xQueueSend(queue_1, &mensaje, portMAX_DELAY); }
}

I understood the problem, there is a conflict when using the same resource the LCD. I introduced a delay in the second loop and matched the flashing times and it works correctly. But now my question is, how to use resources or variables with the two LOOPs simultaneously?.
…….
void loop_tarea1(void * pvParameters)
{ delay(250);
m5.lcd.setCursor(0,70)
m5.Lcd.print("tarea1()")
……..;

I tested n program for ESP32 designed for Arduino ( Esp32/Esp32_dobleNucleo/Esp32_dobleNucleo.ino), and modified it to test in my M5stack. But even though it is checked and loaded correctly. At the start of the job the M5stack is reset every 10", cyclicly. Someone can help me. The code is :

#include"M5Stack.h"
bool bandera = true;

TaskHandle_t Tarea1;

void loop_tarea1(void * pvParameters)
{
m5.lcd.setCursor(0,70);
m5.Lcd.print("tarea1()");
m5.Lcd.print(xPortGetCoreID());
while (1)
{ M5.Lcd.drawRect(150, 120, 122, 110, YELLOW);
delay(1000);
M5.Lcd.drawRect(150, 120, 122, 110, BLUE);
delay(1000); }
}
void setup(){
M5.begin(); // inicio del M5s LCD
m5.Lcd.setTextSize(2);
m5.lcd.setCursor(0,10);
m5.lcd.print("SETUP =");
m5.Lcd.print(xPortGetCoreID());
xTaskCreatePinnedToCore(loop_tarea1, "Tarea1", 10000, NULL, 0, &Tarea1,0);
}
void loop()
{ if(bandera) {
m5.lcd.setCursor(0,30);
m5.Lcd.print("Loop()=");
m5.Lcd.print(xPortGetCoreID());
bandera = false; }

M5.Lcd.drawRect(20,120, 122, 110, BLUE);
delay(400);
M5.Lcd.drawRect(20, 120, 122, 110, YELLOW);
delay(400);
}

@crami25 Thank you very much for this information. I have improved with the capacitor, without changing the potentiometer (I only have that at hand). I'm using the range adjustment at 1.5 v ( ADC_2_5db) and making analogSetSamples(16) , I get this dispersión that would be by 0.2%. It's all right. I'll keep testing, Greetings.

I'm testing the M5stack as a measure of analog signals on the GPIO 35, with good results but I don't know why reason makes a strange noise when measuring.
It's as if the speaker is activated with measurements and makes noise. I can't upload a video to show it. In case anyone has interest I'm measuring the output of a 60k potentiometer, taking 3.3 voltage and Gnd reference.

Thank you very much for your answers help me understand this hardware.
Yes, that's my question. Use M5stack regulator to power the M5Stack and not from charger .
In this case and, it is a last question about this, there will be no problems with the USB input if it is powered by an external battery. In some other case I have had problems connecting the USB, because both 5v sometimes are not exactly and that small difference produced power noises by connecting the USB, and sometimes reestorting the unit.

Best regards

@m5stack said in Charging external batteries type 18650 from usb , M5stack:

PowerC
Thank you for your feedback, ajb2k3 and m5stack.
The Power C is small for the actual project , it is probably better to use standard hardware for charging and only connect the 3.3v voltage on the M5stack. An example like the one I attach photo. But now I think, the output voltage I should use is the 3.3 v and not the 5v. That's it correct?
image url)

I want to do a project based on the M5stack and would like to inform myself if it is possible to recharge an external battery of type 18650 , 3000 mA/h , with the usb from the M5stack. I see in the documentation that is possible to 2.1 A , but I want to be sure .

I want to make an external pull-up connection, with pushbuttons, and an input of a binary expansion module as interruption. It is not clear to me, that the inputs available on the sides, are compatible with these functions.
We have R0,T0,R2,T2,G2,G5, my question is , can all these entries be used freely without damaging the equipment? . Are they connected to other circuits on the board and can be damaged? Even though I've tried to see the schemes that exist, it's not clear to me.
I'd appreciate some information about this.