mics-6814

Platform-agnostic, no_std Rust driver for the MiCS-6814 triple gas sensor.

Converts resistance ratios (Rs/R0) from the sensor's three independent channels into gas concentration estimates (ppm) using calibration curves from the datasheet.

Supported Gases

Gas	Channel	Range
CO	RED	1–1000 ppm
NO2	OX	0.05–10 ppm
NH3	NH3	1–500 ppm
Ethanol	RED	10–500 ppm
H2	RED	1–1000 ppm
CH4	RED	>1000 ppm
C3H8	RED	>1000 ppm
C4H10	RED	>1000 ppm

Usage

use mics_6814::{voltage_to_rs_r0, measure, ChannelReading, Gas};

// Convert ADC voltage to Rs/R0 ratio
let rs_r0 = voltage_to_rs_r0(
    1.65,       // ADC voltage (V)
    3.3,        // Supply voltage (V)
    56_000.0,   // Load resistor (Ω)
    500_000.0,  // R0 from calibration (Ω)
).unwrap();

// Build a reading and measure CO
let reading = ChannelReading { red: rs_r0, ox: 1.0, nh3: 1.0 };
let co = measure(&reading, Gas::CarbonMonoxide).unwrap();
println!("CO: {:.1} ppm", co.ppm);

Calibration

R0 must be measured in clean air after the sensor's warm-up period (~10 minutes). Each channel has its own R0 value.

Features

defmt-03 — enable defmt::Format derives for embedded logging

License