Hardware Pins and Device Address on PCA9543A

New question.

So I'm trying to just test the switch on a breadboard with an Arduino as the master and an oscilloscope to monitor the channels.  When I try my Arduino code I don't read anything on the oscilloscope on either channel.  I'm thinking that it's either that my register addresses are wrong or that perhaps the oscilloscope isn't picking up on the signals.  I tested the oscilloscope with a test code and the oscilloscope read it then so maybe it isn't the problem.

So the device address is: 11100000

My register addresses are 1 and 2 for channel 0 and 1 respectively.  Anything wrong with that? Any ideas of what else could be going on?

Hello Travis,

A few questions:

• Are you able to communicate with the device?
• What pins is the o-scope monitoring?
• If you are able to get an ack and write to the device? If so can you change the register settings and read the values back to verify?

Regards,

Andrew

I haven't checked if I am receiving an ack or not.  I've never had to yet, the only chip I've programmed with is the BQ77PL900 which doesn't ack.  How would I do that?

The oscilloscope is monitoring pins 5 and 9, the sda of each channel.

Here's the code I'm using:

void writei2c(byte registeraddress, byte datastuff)
{
  Wire.beginTransmission(B11100000);
  Wire.write(registeraddress);
  Wire.write(datastuff);
  Wire.endTransmission();
 
  Serial.print("Address: ");
  Serial.print(registeraddress, BIN);
  Serial.print("\tValue: ");
  Serial.println(datastuff, HEX);
}

Hey Andrew,

I was hoping you could help me out again.  I've been able to communicate with the switch with the Arduino, the problem is that it's staying on Channel 0 even when I address Channel 1 first.  Like before I'm monitoring the SDATA pins on each channel on the oscilloscope. 

If you or anyone else looking knows Arduino code, this is what I have setup as of now:

#include <Wire.h>

void setup()
{
  Wire.begin();
  Serial.begin(115200);
}

void loop()
{
  if (Serial.available())
  {
    char c = Serial.read();
    
    if(c == 'a')
    {
      //Write to channel 0
      writei2c(0x01, 1);
    }
    
    if(c == 'b')
    {
      //Write to channel 1
      writei2c(0x02, 1);
    }
  }
}

void writei2c(byte channeladdress, byte datastuff)
{
  //Slave address of PCA9543A
  Wire.beginTransmission(B1110000);
  //Write to control register to select channel
  Wire.write(channeladdress);
  //Wire.beginTransmission(B0010000); would be here if actually talking to BQ
  //Write to the BQ register
  Wire.write((byte)0x00);
  //Write the setting to the BQ register
  Wire.write(datastuff);
  Wire.endTransmission();
 
  //Slave address of PCA9543A
  Wire.beginTransmission(B1110000);
  //Write to control register to reset to default state
  Wire.write(0);
  Wire.endTransmission();
 
  Serial.print("Talking to channel: ");
  Serial.print(channeladdress, BIN);
  Serial.print("\tValue: ");
  Serial.println(datastuff, HEX);
}

Hello Travis,

Can you modify your code to only use channel 1 like below and see if channel one is still not turning on? 

void loop()
{
  if (Serial.available())
  {
    char c = Serial.read();
    
    if(c == 'a')
    {
      //Write to channel 1
      writei2c(0x02, 1);
    }
    
    if(c == 'b')
    {
      //Write to channel 1
      writei2c(0x02, 1);
    }
  }

Regards,

Andrew