I am really a newbie in this kind of thing and I need help. I try to make the Iot scale with Nano ESP32 and HX711 but I can't even make the scale work. I've try this code with UNO board and it work well but when I try on Nano ESP32 it keep showing "HX711 not found." If anyone can help, Thank a lot.
// Calibrating the load cell
#include "HX711.h"
// HX711 circuit wiring
const int LOADCELL_DOUT_PIN = 6;
const int LOADCELL_SCK_PIN = 7;
HX711 scale;
void setup() {
Serial.begin(57600);
scale.begin(LOADCELL_DOUT_PIN, LOADCELL_SCK_PIN);
}
void loop() {
if (scale.is_ready()) {
scale.set_scale();
Serial.println("Tare... remove any weights from the scale.");
delay(5000);
scale.tare();
Serial.println("Tare done...");
Serial.print("Place a known weight on the scale...");
delay(5000);
long reading = scale.get_units(10);
Serial.println("Result: ");
Serial.println(reading);
}
else {
Serial.println("HX711 not found.");
}
delay(1000);
}
Might be..., First I connected the HX711 with VBUS (should be 5V caused I connected Nano ESP32 with my laptop) but the result shows "HX711 not found." But after I changed from VBUS to 3.3V pin, the result keep showing (the scale doesn't response to the weight I put on the scale)
"Tare... remove any weights from the scale.
Tare done...
Place a known weight on the scale...Result:
0"
Is it possible that the Nano ESP32 don't read the "void set up" part? So, the scale begin didn't work. Because I changed the code by adding the Serial.print in void setup but it didn't show in the serial monitor.
#include "HX711.h"
// HX711 circuit wiring
const int LOADCELL_DOUT_PIN = 6;
const int LOADCELL_SCK_PIN = 7;
HX711 scale;
void setup() {
Serial.begin(57600);
scale.begin(LOADCELL_DOUT_PIN, LOADCELL_SCK_PIN);
Serial.print("Starting...");
}
void loop() {
if (scale.is_ready()) {
scale.set_scale();
Serial.println("Tare... remove any weights from the scale.");
delay(5000);
scale.tare();
Serial.println("Tare done...");
Serial.print("Place a known weight on the scale...");
delay(5000);
long reading = scale.get_units(10);
Serial.println("Result: ");
Serial.println(reading);
}
else {
Serial.println("HX711 not found.");
}
delay(1000);
}
OK the M5 does not have Vdd.
The Nano ESP is 3.3V I/O so you must use 3.3V.
Connecting the Nano pins to 5V may have damaged them so first try to use different pins.
I use pin 7 and 8 because pin 2 and 3 in Nano ESP is analog pin. The result is the same. Keep printing "HX711 reading: 0" even I put something on the scale, it read as 0
No D2 nad D3 are digital pins
I think you have your pin numbers mixed up
Show a diagram of how you have the scale connected.
Please post a datasheet for the scale.
Do you mean by how I connect ESP, HX711, and scale? here is the diagram. and I did change the pin to D2 and D3 but the result is the same. I also change the PIN number in the code to D2 (5) and D3 (6). There are a little confusion in the pin number in Nano ESP. The numbers are different from the one showing in the board.
what is data sheet for the scale?
But if scale is bad or connect it wrong, it shouldn't work on UNO. And I just find something there is different in the speed of UNO and ESP32 which might related, but I didn't get it?
You are correct.
Then the only difference is that the Uno is 5V and the ESP is 3.3V and there is nothing in the M5 stack documentation that says it will work at 3.3V
That's the data sheet for the HX711 part. The M5 stack module makes no claims about 3.3V.
The exitation voltage for the loadcell may not be high enough when that module is used with 3.3V
I have the espressif ESP32 core installed which includes the Arduino Nano ESP32 board and it does not have those options. It works with either the GPIO numbers or the Dn and An designations.
