Having trouble connecting two digital pots MCP 41H51503 to Arduino Mega

[sulfur101]

#include <SPI.h>

static const int spiClk = 1000000;
byte address = 0x00;
byte address2 = 0x01; // Address for the second digital pot
SPIClass *hspi = NULL;

void setup()
{
  pinMode(53, OUTPUT); // Set SS (Slave Select) pin for the first pot to 53 on Mega
  pinMode(45, OUTPUT); // Set SS pin for the second pot to 45
  hspi = new SPIClass(SPI);
  hspi->begin();
}

void loop()
{
  int counter = 0;
  while (1) {
    for (int i = 0; i <= 255; i++)
    {
      digitalPotWrite(53, address, i); // Control the first pot
      if (counter <= 1) {
        digitalPotWrite(45, address2, 255 - i); // Control the second pot
      }
      delay(10);
    }
    counter++;
    delay(500);
    for (int i = 255; i >= 0; i--)
    {
      digitalPotWrite(53, address, i); // Control the first pot
      digitalPotWrite(45, address2, 255 - i); // Control the second pot
      delay(10);
    }
  }
  counter = 0;
}

void digitalPotWrite(int csPin, byte address, int value)
{
  hspi->beginTransaction(SPISettings(spiClk, MSBFIRST, SPI_MODE0));
  digitalWrite(csPin, LOW); // Select the MCP4131
  hspi->transfer(address);
  hspi->transfer(value);
  digitalWrite(csPin, HIGH); // Deselect the MCP4131
  hspi->endTransaction();
}

the code that i have are two digital potentiometers and they are just not working and are my SCK,SDI pins supposed to be the same?

 

[KlausST]

Hi,

It's simpler to use a dual pot.
But you may use two i deoendent.

The problem here is:
* we don't see how you wired it (schematic)
* we don't see which pins you used for the SPI in software
* we don't have a clear error description, including test setup

I see no need to beginTransaction and endTransaction for every single access. I mean: the setup is always the same.

Klaus