robtillaart / ad524x Goto Github PK

Hi Everyone,
I'm looking for guidance to know what exactly the reason that my circuit is not working as expected.

1. I have connected to AD5242 IC as per the datasheet guidance and integrated with ATTINY402 using I2C bus. As always pull-up registers and other connections are taken care.
2. I currently have followed only RobTillaart AD524X library and its example codes. Initially I tested with "isConnected" example code and it responded true ('1') on serial monitor. Later I ever tested with logic outputs "O1 & O2" and they are working absolutely fine.

• Now the problem is, Even after RDAC1 & RDAC2 registers are being updated with "200" value, there is no change in voltage drop at W1 & W2 with respect to B1 & B2 (Ground connected). I did some survey online and tried all possible way, but unable to find a solution to this. :(
• Even I tried reading RDAC register back for validation, surprisingly register hold "200" in it. However, A1, W1 & B1 terminals are not at all changing.

PFA schematics and code for your reference.

I'm very happy if anyone over GitHub can help me to solve this problem.

Thanks in advance,
Vaibhav Sugandhi

• check examples
• update AD542X_LIB_VERSION
• link to 5245 library.

Hi, in title implicitly states AD5245 is supported, but did not see it written - is this likely to work? AD5245 is one of the top 5 digital potentiometers supported by jlcpcb assembly service currently

Hello! Is the data in the "I2C address" table correct? AD0 and AD1 do not need to be swapped? In the datasheet AD1 is the high bit of the address.

I'm attempting to use this library with a Teensy 4.0 and the potentiometer keeps reading the midpoint value. Simply put, I can't seem to get this to work. It seems to be a communication error but I've noticed the read commands don't actually read from the AD524X but simply return what you last set the value as.

I have finally gotten to the bottom of why the library doesn't work on an Adafruit Feather RP2040! The problem is here:

uint8_t AD524X::send(const uint8_t cmd, const uint8_t value)
{
  Wire.beginTransmission(_address);
  Wire.write(cmd);
  Wire.write(value);
  return Wire.endTransmission();
}

This code uses the default Wire channel rather then the one specified during initialization. Changing the code to this, fixed the problem:

uint8_t AD524X::send(const uint8_t cmd, const uint8_t value)
{
  _wire->beginTransmission(_address);
  _wire->write(cmd);
  _wire->write(value);
  return _wire->endTransmission();
}

Although I am not using it, I believe this:

uint8_t AD524X::readBackRegister()
{
  Wire.beginTransmission(_address);
  Wire.endTransmission();
  Wire.requestFrom(_address, (uint8_t)1);
  return Wire.read();
}

should be changed to this:

uint8_t AD524X::readBackRegister()
{
  _wire->beginTransmission(_address);
  _wire->endTransmission();
  _wire->requestFrom(_address, (uint8_t)1);
  return _wire->read();
}

Thanks again for all the hard work in producing this library.

hi
is it possible in some way (ex. a read instruction) to know the type of IC (if 41 or 42) and its pots type (10k, 100k or 1M)?

See PCF8574

just a wrapper would be OK if used in base class (or is this error prone ...?)

uint8_t AD524X::write(const uint8_t value)
{
  write(0, value);
};

or if only in AD5421 it might be optimized.

uint8_t AD5241::write(const uint8_t value)
{
  // apply the output lines
  uint8_t cmd = AD524X_RDAC0 | _O1 | _O2;
  _lastValue[0] = value;
  return send(cmd, value);
}

Thanks for creating a great library!

I am trying to use the library on an Adafruit RP2040 Feather.
There are two I2C channels on this board. I initialize the library for the second channel (Wire1) as that is the one the AD5242 is connected to:

AD5242 AD01(0x2C, &Wire1);

The setup code indicates that the AD5242 is found. More specifically, this code:

      b = AD01.begin();
      Serial.println(b ? "Begin: true" : "Begin: false");
      Serial.println(AD01.isConnected());

produces this output:
Begin: true
1

However, when I try to write to the AD5242 there are errors:

      int a = AD01.write(0, 100);
      int b = AD01.write(1, 100 );
      char buff[256];
      sprintf(buff,"Write 1: %d\tWrite 2: %d\n", a, b);
      Serial.println(buff);

The output is:
Write 1: 4 Write 2: 4

From the Arduino documentation for Wire, I believe that a return value of 4 means "other error"

I know that the hardware works properly as everything works correctly when I used an ESP32 instead of the RP2040. My board is designed as a feather wing so that I can simply swap feather processors. (For the ESP32 I initialize with AD5242 AD01(0x2C); )

Any suggestions?