How to read a chain of TMP421 Temperature Sensors with an Arduino
I recently made some minor modifications to the Liquidware Arduino Temperature Sensor Library which is designed to read from a single TMP421 sensor from Modern Device (the chip is made by TI). You can download my modified library, LibTemperature2.
Instantiate a LibTemperature2 object with the address of the sensor, which is determined by the A0 and A1 pins on the breakout board according to this chart:
‘0’ means Ground, ‘1’ means Vcc, and ‘Float’ means unconnected. So to address 0x1C (0011100b), connect A0 to ground and leave A1 unconnected. Note that the default address is 0x2A.