pamoja-sensors

Datasheet-anchored decoders for eleven parts: the BME280, BMP280, DS18B20, HDC1080, INA219, INA226, ADS1115, OPT3001, SCD4x, SHT3x, and TMP117. One capability of pamoja, one memory-safe Rust core with bindings for TypeScript, Python, and C#.

Install

pip install pamoja-sensors

from pamoja import sensors

This pulls in pamoja-native, the compiled engine. pip install pamoja is the whole framework in one package.

Example

The script the test suite runs, spliced here as it ran.

From bindings/python/guides/sensors.py:

from pamoja.core import PamojaError
from pamoja.sensors import ds18b20, ina219

# Stand-ins for the two parts. On a running node the thermometer's nine bytes come off
# the 1-Wire bus and the monitor's registers off I2C; here the library builds what each
# would send, so the program runs with nothing plugged in.
thermometer = ds18b20.build_scratchpad(25.0625, 12, 75, -10)

# The monitor is set up for 1 mA per count across a 2 milliohm shunt, the load its
# datasheet's worked design example describes: 11.98 V, 10 A, and 119.8 W.
CURRENT_LSB = 1_000
bus = ina219.bus_register(11_980)
current = ina219.current_register(10_000_000, CURRENT_LSB)
power = ina219.power_register(119_800_000, CURRENT_LSB)

# Everything below is the node's own code. The thermometer checksums every read, so a
# reading is verified before it is believed.
reading = ds18b20.parse_scratchpad(thermometer)
print(f"temperature  {reading.celsius:.4f} C")
print(f"resolution   {reading.resolution_bits} bits")
print(f"alarms       {reading.alarm_high} / {reading.alarm_low} C")

# The monitor computes nothing until it has been told what shunt it is across.
print(f"calibration  0x{ina219.calibration(CURRENT_LSB, 2):04X}")
print(f"bus          {ina219.bus_millivolts(bus)} mV")
print(f"current      {ina219.current_microamps(current, CURRENT_LSB) // 1_000} mA")
print(f"power        {ina219.power_microwatts(power, CURRENT_LSB) // 1_000} mW")

# A bit flipped on a long 1-Wire run fails the checksum, so the node repeats the read
# instead of logging a temperature a couple of degrees off.
corrupted = bytearray(thermometer)
corrupted[0] ^= 1
try:
    ds18b20.parse_scratchpad(bytes(corrupted))
    print("corrupt read accepted, which should never happen")
except PamojaError as error:
    print(f"corrupt read rejected: {error}")

The same capability in every language

Documentation

• pamoja.sensors reference, every class and function in this module.
• The Sensor drivers guide, with the same example in Rust, TypeScript, and C#.
• Every capability, and the install page.

License

MIT