AIN4-20mA Unit to Arduino Nano Every

spectrad

I am trying to talk to the module using a Nano Every using the standard wire example, I get no output at all. If I use a sniffing sketch, it detects the device on 0x55 so it is visible on the bus.

#include <Wire.h>

void setup() {
  Wire.begin(8);        // join i2c bus (address optional for master)
  Serial.begin(9600);  // start serial for output
}

void loop() {
  Wire.requestFrom(0x55, 8);    // request 8 bytes from slave device 0x55

  while (Wire.available()) { // slave may send less than requested
    char c = Wire.read(); // receive a byte as character
    Serial.print(c,DEC);         // print the character
  }

  delay(250);
}

I have a 4-20mA current source which I can measure, so I am confident I have a variable input.

I have not used I2C before, I am confident the Arduino libraries are correct, so any pointers to what it might be would be appreciated. Thanks.

robski

@spectrad said in AIN4-20mA Unit to Arduino Nano Every:

I am trying to talk to the module using a Nano Every using the standard wire example, I get no output at all. If I use a sniffing sketch, it detects the device on 0x55 so it is visible on the bus.
#include <Wire.h>

void setup() {
  Wire.begin(8);        // join i2c bus (address optional for master)
  Serial.begin(9600);  // start serial for output
}

void loop() {
  Wire.requestFrom(0x55, 8);    // request 8 bytes from slave device 0x55

  while (Wire.available()) { // slave may send less than requested
    char c = Wire.read(); // receive a byte as character
    Serial.print(c,DEC);         // print the character
  }

  delay(250);
}
I have a 4-20mA current source which I can measure, so I am confident I have a variable input.

I have not used I2C before, I am confident the Arduino libraries are correct, so any pointers to what it might be would be appreciated. Thanks.

not sure if you can marry M5stack sensor/module with diff MCUs than esp32? maybe I'm wrong here.

spectrad

@robski I assumed as it was I2C then anything that had an I2C port should work as it's a standard protocol, but I could be wrong as well.

Cognitive5525

@spectrad have you tried with the M5Stack example here?

spectrad

@Cognitive5525 said in AIN4-20mA Unit to Arduino Nano Every:

@spectrad have you tried with the M5Stack example here?

No as I am not using an M5Stack, I am trying to use an Arduino Nano Every.

robski

@Cognitive5525 said in AIN4-20mA Unit to Arduino Nano Every:

@spectrad have you tried with the M5Stack example here?

he doesn't have M5Stack controller, only M5Stack sensor trying to read back to Arduino NANO so not esp32 board.

Cognitive5525

@spectrad said in AIN4-20mA Unit to Arduino Nano Every:

@spectrad have you tried with the M5Stack example here?
No as I am not using an M5Stack, I am trying to use an Arduino Nano Every.

Ah sorry I overlooked that, but even though you're not using a M5stack MC I still believe that you might be able to get some "inspiration" from it. Have a look at the module MODULE_4_20MA in src-folder. As far as I can see it does not rely on any special M5stack libraries at this level.

spectrad

@Cognitive5525 said in AIN4-20mA Unit to Arduino Nano Every:

@spectrad said in AIN4-20mA Unit to Arduino Nano Every:
@spectrad have you tried with the M5Stack example here?
No as I am not using an M5Stack, I am trying to use an Arduino Nano Every.
Ah sorry I overlooked that, but even though you're not using a M5stack MC I still believe that you might be able to get some "inspiration" from it. Have a look at the module MODULE_4_20MA in src-folder. As far as I can see it does not rely on any special M5stack libraries at this level.

Although you are not wrong about getting inspiration from it, using the Arduino Wire functions I should get something (and they do detect the device), the M5 library really just decodes the values its reading using the M5 version of the wire library (I assume, I don't know the M5).

I am not reading anything from the module using I2c (a standard protocol), that's the bit I don't understand, if I can read some data back, I can manipulate it from there to get a reading, it's just I don't get data, so I am left scratching my head.

Cognitive5525

I think the MODULE_4_20MA (in the src folder) is only using some standard libraries:
From top src/MODULE_4_20MA.h:

#ifndef __MODULE_4_20MA_H
#define __MODULE_4_20MA_H

#include "Arduino.h"
#include "Wire.h"

Try to download only the two files in the src-folder and see if you can include them into your project and compile.

Also: If you look at the code in src/MODULE_4_20MA.cpp you'll see that they include some register addresses, maybe that is required for this AIN4-20mA unit?