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caternusoncaternuson
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add code for multi i2c guide
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‎I2C_Multiple_Same_Address/arduino/multi_bme280_2x/multi_bme280_2x.ino

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// SPDX-FileCopyrightText: 2022 Carter Nelson for Adafruit Industries
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//
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// SPDX-License-Identifier: MIT
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#include <Adafruit_BME280.h>
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// For each device, create a separate instance.
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Adafruit_BME280 bme1; // BME280 #1 @ 0x77
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Adafruit_BME280 bme2; // BME280 #2 @ 0x76
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void setup() {
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Serial.begin(9600);
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while(!Serial);
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Serial.println(F("Two BME280 Example"));
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// NOTE: There's no need to manually call Wire.begin().
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// The BME280 library does that in its begin() method.
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// In the call to begin, pass in the I2C address.
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// If left out, the default address is used.
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bme1.begin(); // use the default address of 0x77
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bme2.begin(0x76); // specify the alternate address of 0x76
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}
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void loop() {
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float pressure1, pressure2;
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// Read each device separately
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pressure1 = bme1.readPressure();
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pressure2 = bme2.readPressure();
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Serial.println("------------------------------------");
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Serial.print("BME280 #1 Pressure = "); Serial.println(pressure1);
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Serial.print("BME280 #2 Pressure = "); Serial.println(pressure2);
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delay(1000);
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}

‎I2C_Multiple_Same_Address/arduino/multi_bme280_3x/multi_bme280_3x.ino

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// SPDX-FileCopyrightText: 2022 Carter Nelson for Adafruit Industries
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//
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// SPDX-License-Identifier: MIT
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#include <Adafruit_BME280.h>
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#define TCAADDR 0x70
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// For each device, create a separate instance.
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Adafruit_BME280 bme1; // BME280 #1
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Adafruit_BME280 bme2; // BME280 #2
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Adafruit_BME280 bme3; // BME280 #3
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// Helper function for changing TCA output channel
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void tcaselect(uint8_t channel) {
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if (channel > 7) return;
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Wire.beginTransmission(TCAADDR);
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Wire.write(1 << channel);
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Wire.endTransmission();
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}
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void setup() {
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Serial.begin(9600);
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while(!Serial);
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Serial.println(F("Three BME280 Example"));
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// NOTE!!! VERY IMPORTANT!!!
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// Must call this once manually before first call to tcaselect()
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Wire.begin();
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// Before using any BME280, call tcaselect to set the channel.
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tcaselect(0); // TCA channel for bme1
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bme1.begin(); // use the default address of 0x77
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tcaselect(1); // TCA channel for bme2
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bme2.begin(); // use the default address of 0x77
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tcaselect(2); // TCA channel for bme3
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bme3.begin(); // use the default address of 0x77
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}
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void loop() {
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float pressure1, pressure2, pressure3;
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// Read each device separately
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tcaselect(0);
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pressure1 = bme1.readPressure();
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tcaselect(1);
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pressure2 = bme2.readPressure();
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tcaselect(2);
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pressure3 = bme3.readPressure();
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Serial.println("------------------------------------");
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Serial.print("BME280 #1 Pressure = "); Serial.println(pressure1);
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Serial.print("BME280 #2 Pressure = "); Serial.println(pressure2);
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Serial.print("BME280 #3 Pressure = "); Serial.println(pressure3);
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delay(1000);
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}

‎I2C_Multiple_Same_Address/arduino/multi_bme280_4x/multi_bme280_4x.ino

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// SPDX-FileCopyrightText: 2022 Carter Nelson for Adafruit Industries
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//
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// SPDX-License-Identifier: MIT
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#include <Adafruit_BME280.h>
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#define TCAADDR 0x70
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// For each device, create a separate instance.
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Adafruit_BME280 bme1; // BME280 #1
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Adafruit_BME280 bme2; // BME280 #2
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Adafruit_BME280 bme3; // BME280 #3
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Adafruit_BME280 bme4; // BME280 #4
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// Helper function for changing TCA output channel
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void tcaselect(uint8_t channel) {
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if (channel > 7) return;
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Wire.beginTransmission(TCAADDR);
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Wire.write(1 << channel);
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Wire.endTransmission();
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}
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void setup() {
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Serial.begin(9600);
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while(!Serial);
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Serial.println(F("Four BME280 Example"));
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// NOTE!!! VERY IMPORTANT!!!
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// Must call this once manually before first call to tcaselect()
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Wire.begin();
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// Before using any BME280, call tcaselect to select its output channel
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tcaselect(0); // TCA channel for bme1
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bme1.begin(); // use the default address of 0x77
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tcaselect(1); // TCA channel for bme2
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bme2.begin(); // use the default address of 0x77
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tcaselect(2); // TCA channel for bme3
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bme3.begin(); // use the default address of 0x77
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tcaselect(3); // TCA channel for bme4
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bme4.begin(); // use the default address of 0x77
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}
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void loop() {
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float pressure1, pressure2, pressure3, pressure4;
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// Read each device separately
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tcaselect(0);
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pressure1 = bme1.readPressure();
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tcaselect(1);
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pressure2 = bme2.readPressure();
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tcaselect(2);
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pressure3 = bme3.readPressure();
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tcaselect(3);
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pressure4 = bme4.readPressure();
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Serial.println("------------------------------------");
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Serial.print("BME280 #1 Pressure = "); Serial.println(pressure1);
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Serial.print("BME280 #2 Pressure = "); Serial.println(pressure2);
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Serial.print("BME280 #3 Pressure = "); Serial.println(pressure3);
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Serial.print("BME280 #4 Pressure = "); Serial.println(pressure4);
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delay(1000);
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}

‎I2C_Multiple_Same_Address/circuitpython/multi_bme280_2x/code.py

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# SPDX-FileCopyrightText: 2022 Carter Nelson for Adafruit Industries
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#
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# SPDX-License-Identifier: MIT
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import time
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import board
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from adafruit_bme280 import basic as adafruit_bme280
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# Get the board's default I2C port
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i2c = board.I2C()
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# Create each sensor instance
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bme1 = adafruit_bme280.Adafruit_BME280_I2C(i2c) # default 0x77 address
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bme2 = adafruit_bme280.Adafruit_BME280_I2C(i2c, 0x76) # alternate 0x76 address
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print("Two BME280 Example")
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while True:
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# Access each sensor via its instance
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pressure1 = bme1.pressure
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pressure2 = bme2.pressure
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print("-"*20)
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print("BME280 #1 Pressure =", pressure1)
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print("BME280 #2 Pressure =", pressure2)
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time.sleep(1)

‎I2C_Multiple_Same_Address/circuitpython/multi_bme280_3x/code.py

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# SPDX-FileCopyrightText: 2022 Carter Nelson for Adafruit Industries
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#
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# SPDX-License-Identifier: MIT
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import time
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import board
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import adafruit_tca9548a
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from adafruit_bme280 import basic as adafruit_bme280
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# Create I2C bus as normal
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i2c = board.I2C()
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# Create the TCA9548A object and give it the I2C bus
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tca = adafruit_tca9548a.TCA9548A(i2c)
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#--------------------------------------------------------------------
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# NOTE!!! This is the "special" part of the code
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#
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# Create each BME280 using the TCA9548A channel instead of the I2C object
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bme1 = adafruit_bme280.Adafruit_BME280_I2C(tca[0])
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bme2 = adafruit_bme280.Adafruit_BME280_I2C(tca[1])
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bme3 = adafruit_bme280.Adafruit_BME280_I2C(tca[2])
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#--------------------------------------------------------------------
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print("Three BME280 Example")
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while True:
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# Access each sensor via its instance
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pressure1 = bme1.pressure
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pressure2 = bme2.pressure
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pressure3 = bme3.pressure
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print("-"*20)
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print("BME280 #1 Pressure =", pressure1)
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print("BME280 #2 Pressure =", pressure2)
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print("BME280 #3 Pressure =", pressure3)
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time.sleep(1)

‎I2C_Multiple_Same_Address/circuitpython/multi_bme280_4x/code.py

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# SPDX-FileCopyrightText: 2022 Carter Nelson for Adafruit Industries
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#
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# SPDX-License-Identifier: MIT
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import time
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import board
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import adafruit_tca9548a
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from adafruit_bme280 import basic as adafruit_bme280
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# Create I2C bus as normal
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i2c = board.I2C()
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# Create the TCA9548A object and give it the I2C bus
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tca = adafruit_tca9548a.TCA9548A(i2c)
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#--------------------------------------------------------------------
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# NOTE!!! This is the "special" part of the code
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#
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# Create each BME280 using the TCA9548A channel instead of the I2C object
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bme1 = adafruit_bme280.Adafruit_BME280_I2C(tca[0])
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bme2 = adafruit_bme280.Adafruit_BME280_I2C(tca[1])
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bme3 = adafruit_bme280.Adafruit_BME280_I2C(tca[2])
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bme4 = adafruit_bme280.Adafruit_BME280_I2C(tca[3])
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#--------------------------------------------------------------------
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print("Four BME280 Example")
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while True:
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# Access each sensor via its instance
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pressure1 = bme1.pressure
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pressure2 = bme2.pressure
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pressure3 = bme3.pressure
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pressure4 = bme4.pressure
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print("-"*20)
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print("BME280 #1 Pressure =", pressure1)
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print("BME280 #2 Pressure =", pressure2)
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print("BME280 #3 Pressure =", pressure3)
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print("BME280 #4 Pressure =", pressure4)
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time.sleep(1)

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