Datasheet

Wire.write(1 << i);
Wire.endTransmission();
}
// standard Arduino setup()
void setup()
{
while (!Serial);
delay(1000);
Wire.begin();
Serial.begin(115200);
Serial.println("\nTCAScanner ready!");
for (uint8_t t=0; t<8; t++) {
tcaselect(t);
Serial.print("TCA Port #"); Serial.println(t);
for (uint8_t addr = 0; addr<=127; addr++) {
if (addr == TCAADDR) continue;
uint8_t data;
if (! twi_writeTo(addr, &data, 0, 1, 1)) {
Serial.print("Found I2C 0x"); Serial.println(addr,HEX);
}
}
}
Serial.println("\ndone");
}
void loop()
{
}
For example, running it on the above setup will give you:
© Adafruit Industries
https://learn.adafruit.com/adafruit-tca9548a-1-to-8-i2c-multiplexer-
breakout
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