Thanks

0x76

Hello,
i get a problem with Pa.HUB i connected to it ENV.III. I get Temp and Hum ok but i get -482827.3 for pressure.
What is wrong ??

I am new to development boards however I am an experienced platform developer.

I have a Core2 and I want to use PaHUB and add couple of more units to read. I have no problem reading data via using Wire command over PaHUB like using 4way Relay.

However, I have no idea how to use BMP and SHT over PaHUB. I have tried combining examples without any luck and tried above without any luck.

Question is after portselect, how come bmp access to right address? If you can point me to any direcon, I will be grateful.

Cheers.

The M5Stck was connected to the Base BTC. The PaHUB was connected to the red Grove port and two ENV sensors were connected to channels 0 and 1 of the PaHUB. I then installed my application, but the ENV sensors connected to the PaHUB didn't deliver any values. When I queried the channels 2-5 of PaHUB I received values, but all were the same.

So I disconnected the M5Stack from the Base BTC; afterwards I received the temperature and humidity of the two ENV sensors connected to channels 0 and 1 of the PaHUB.

Is it somehow possible to connect the M5Stack to the Base BTC but read the sensors connected to the PaHUB? Or do I need the PbHUB to achieve this?

Best regards
Thomas

When I run the PaHUB demo, it shows the addresses 0x5C, 0x70, 0x75 and 0x76 for channel 0 and 1, and 0x5C, 0x70, 0x75 for the remaining channels.

I my own program, I added the class TCA9548A and DHT22 (I renamed TCA9548A to PaHUB).

My setup function looks like this:

#define PaHub_I2C_ADDRESS  0x70
#define ENV_I2C_ADDRESS    0x76

PaHUB pahub;

void setup() {
  ez.begin();
  Wire.begin();
  pahub.address(PaHub_I2C_ADDRESS);
}

I defined a struct for my sensors:

struct Sensor {
  uint8_t channel;
  DHT12   device;
  char*   name;
};

and an array of the struct which is initialized that way:

struct Sensor sensors[] = {
  {0, DHT12(CELSIUS, ENV_I2C_ADDRESS), "Left"},
  {1, DHT12(CELSIUS, ENV_I2C_ADDRESS), "Hotspot"},
  {2, DHT12(CELSIUS, ENV_I2C_ADDRESS), "Right"},
  {3, DHT12(CELSIUS, ENV_I2C_ADDRESS), "Left"},
  {4, DHT12(CELSIUS, ENV_I2C_ADDRESS), "Hotspot"},
  {5, DHT12(CELSIUS, ENV_I2C_ADDRESS), "Right"}
};

This is how I'm reading the sensors:

struct SensorValues readSensor(int channel) {
  struct SensorValues sensorValues;
  struct Sensor sensor = sensors[channel];
  uint8_t returnCode = pahub.selectChannel(sensor.channel);

  Serial.println(" ---------- readSensor() ----------");
  Serial.print("pahub.selectChannel(");
  Serial.print(sensor.channel);
  Serial.print(") = ");
  Serial.println(returnCode);

  if (returnCode == 0) {
    sensorValues.temperature = sensor.device.readTemperature();
    sensorValues.humidity = sensor.device.readHumidity(); 
  }

  Serial.println(" ---------- readSensor() ----------");

  return sensorValues;
}

Unfortunately I'm receiving always 0 for both the temperature and the humidity.
Could anybody please give me a hint what I'm doing wrong?

Thanks & Best regards
Thomas

ENV:https://github.com/m5stack/M5Stack/tree/master/examples/Unit/ENV
PaHUB：https://github.com/m5stack/M5Stack/tree/master/examples/Unit/PaHUB

// Defines
#define PaHub_I2C_ADDRESS	0x70
#define ENV1_ADD	<Your I2C address>
#define ENV2_ADD	<Your I2C address>
#define ENV3_ADD	<Your I2C address>
#define ENV4_ADD	<Your I2C address>
...

I also found the I2C 1 Hub to 6 Expansion Unit. I guess that this would be a better choice to connect more than one ENV unit to a M5 Stack device. Am I right?

Correct. With the other 1 to 3 Hub, you would have address conflicts. Use the 1 to 6 Expansion Unit.