kfricke / micropython-mcp9808

MicroPython driver for the Microchip MCP9808 temperature sensor

micropython-mcp9808

This repository contains a MicroPython "driver" implementation for the MCP9808 temperature sensor from Microchip.

Implemented

• Reading the temperature value in degree celsius. The get_temp() method supports floating point values and the get_temp_int() method does not use floating point arythmetic at all and does return a tuple of decimal and fraction parts of the temperature reading.

• Shutdown mode to save power. When not in shutdown mode the sensor does draw 200-400 uA. Data acquisition can only be stopped in the so called "shutdown mode". In this mode communication is still possible using I2C.

• Changing the data acquisition resolution and duration. On power up the sensor is set to maximum resolution.

  Mode Name	Resolution	Duration	Samples / sec
  T_RES_MIN	+-0.5 °C	30 ms	33
  T_RES_LOW	+-0.25 °C	65 ms	15
  T_RES_AVG	+-0.125 °C	130 ms	7
  T_RES_MAX	+-0.0625 °C	250 ms	4

• Alert mode: boundaries are defined by using set_alert_boundary_temp(). set_alert_mode(self, enable_alert, output_mode, polarity, selector) allows to enable/disable alert functionality, set the desired output mode to comparator or interrupt, switch te polarity between active-low or active-high (pull-up resistor required!) as well as what boundaries should trigger an alert.

Not yet implemented

• hysteresis