Hardware#

Reports humidity, pressure and temperature as raw counts plus per-chip calibration coefficients, which the driver compensates.

A digital thermometer that returns Celsius over a single data line, each part carrying its own 64-bit serial code so a bus can hold many.

Measures the drop across an external shunt and the bus voltage, and reports current and power once its calibration register is set.

A 16-bit delta-sigma ADC that digitises four single-ended or two differential inputs through a programmable gain amplifier.

Reports humidity and temperature as calibrated 16-bit words, each followed by a CRC-8, which the driver checks and converts with the fixed linear formulas.

A photoacoustic NDIR CO2 sensor with a built-in humidity and temperature sensor; every word it sends carries a CRC-8 the driver checks.

A 16-bit digital thermometer accurate to ±0.1 °C with no calibration, with programmable alert limits, a user offset, and 48 bits of EEPROM.

Reports humidity and temperature as 16-bit fractions of full scale with no per-chip calibration, which the driver decodes in exact integer arithmetic alongside the configuration register.

A single-chip lux meter filtered to the human eye's response that reports illuminance as a 4-bit exponent and 12-bit mantissa, ranging itself across twelve full-scale settings.

Measures the drop across a shunt and the bus voltage on either side of the load, reports current and power once calibrated, and drives an alert pin from one programmable limit.

Reports barometric pressure and temperature as 20-bit raw counts plus per-chip calibration coefficients, which the driver compensates; the BME280 without the humidity element.

A 16-channel PWM generator that produces servo and dimming pulses; each output sinks 25 mA, so load current is switched by an external driver.

A Darlington array that switches the coil current directly, for the four-wire steppers the coil sequencer walks a pattern across.

A bipolar stepper driver that turns one pulse on STEP into one microstep, sequencing the coils and regulating current in hardware.

A bipolar stepper driver with two H-bridges and an indexer, taking step and direction down to 1/32 step.

The two-wire addressable bus that hangs sensors and peripherals off one controller; the address a chip answers on is what the gpio crate carries.

A full-duplex synchronous link between a controller and one selected peripheral at a time; no standard defines it, so pin names, timing and rate come from each device's own datasheet.

Request and reply in binary frames over a two-wire trunk, the way meters, drives and PLCs are wired along one cable.

The multi-master vehicle bus whose identifier both labels a message and arbitrates access. The standard itself is paid, so the figures below are what its catalogue page states and what the crate implements.

The higher-layer protocol trucks, buses and off-highway machines run over CAN, defined as a set of SAE documents under one top-level recommended practice.

The sub-GHz LoRa and FSK transceiver on most 137 to 1020 MHz end devices, and the radio a pamoja airtime budget is computed for.

The later sub-GHz LoRa transceiver, covering 150 to 960 MHz with a higher power amplifier and a much lower receive current.

The document that fixes the channel plan, data rates, transmit limits and maximum payload a LoRaWAN device must obey in each regulatory region.

Espressif's connectionless protocol: short packets straight between Wi-Fi devices with no access point and no association step.

The gateway-class Linux board: the full std build, every transport, and the dashboard.

The small, low-cost Linux board, running the same std build as the Pi 5 on the same 40-pin footprint.

The Wi-Fi and Bluetooth microcontroller behind most small sensor nodes, with the buses above and a CAN controller on chip.

Open autopilot firmware for copters, planes, rovers and submarines; the firmware is free, and the flight controller it runs on is what costs money.

Open autopilot firmware for multirotors, fixed wing, VTOL, helicopters and rovers, under a permissive licence; again, the board is the cost.

The open hardware standard that fixes flight controller pin-outs, connectors and layout so boards from different vendors interchange; a board built to it is what costs money.

The bare-metal target: CI cross-compiles every no_std crate for thumbv7em-none-eabihf, which is this core with its floating-point unit and no operating system.