Service MQTT API (DAQAstra)

All DAQAstra services communicate over MQTT using a publish / subscribe model.

A service topic prefix is always:

{firmware_name}/{service_name}

Spaces in service_name are converted to underscores.

Below each service lists:

Command (subscription) topics it listens on
Publish (output / status) topics it emits
Payload schemas (JSON unless otherwise noted)
Notes / semantics

Topic layouts are derived from the code in config-schema/src/schema/topics.rs (see the large comment block there) and the message structs in config-schema/src/messaging/*.rs.
If a field is optional it may be omitted or sent as null.

Version note: This document supersedes older copies that mixed legacy names. Always regenerate if message structs change.

Conventions

Term	Meaning
`{prefix}`	`{firmware_name}/{service_name}`
Boolean	`true` / `false`
Milliseconds	Unsigned 16/32-bit depending on context (see field)
Temperature	Degrees Celsius unless otherwise stated
Percent / Ratio	0.0 – 1.0 floating-point
Integer ranges	Unless stated, unsigned and constrained by underlying hardware width

actuator

Generic actuator command, state and fault reporting

Topic Suffix	Dir	Kind	Example JSON
`/command`	in	cmd	`{ "command": "OPEN" }`
`/state`	out	telemetry	`{ "command": "OPEN", "state": "OPEN", "success": true }`
`/fault`	out	event	`{ "error": "Unknown State", "state": "Unknown", "attempted_command": "OPEN" }`

Payload Schemas

`/command` `ActuatorCommand`

{ "command": "OPEN" }

`/state` `ActuatorState`

{ "command": "OPEN", "state": "OPEN", "success": true }

`/fault` `ActuatorFault`

{ "error": "Unknown State",  "state": "Unknown", "attempted_command": "OPEN" }

aht20

AHT20 humidity / temperature sensor data

Topic Suffix	Dir	Kind	Example JSON
``	out	telemetry	`{ "temperature": { "value":22.8, "unit":"C" }, "humidity": { "value":40.1, "unit":"%RH" }, "dewpoint": { "value":9.7,…`

Payload Schemas

`` `Aht20Data`

{ "temperature": { "value":22.8, "unit":"C" }, "humidity": { "value":40.1, "unit":"%RH" }, "dewpoint": { "value":9.7, "unit":"C" } }

analog_in

Analog input channel telemetry and configuration

Topic Suffix	Dir	Kind	Example JSON
`''`	out	telemetry	`{ "value": 0.123, "unit": "V" }`
`/config`	in	cmd	`{ "conversion": { "Polynomial": [0.0, 1.0, 0.0, 0.0] } }`

Payload Schemas

`''` `AnalogInData`

{ "value": 0.123, "unit": "V" }

`/config` `AnalogConversionConfig`

{ "conversion": { "Polynomial": [0.0, 1.0, 0.0, 0.0] } }

analog_out

DAC / analog output configuration and feedback

Topic Suffix	Dir	Kind	Example JSON
`/config`	in	cmd	`{ "value": 2.5, "max_volts": 5.0, "enabled": true }`
`/response`	out	telemetry	`{ "value": 2.5, "max_volts": 5.0, "enabled": true, "error": null }`

Payload Schemas

`/config` `DacConfig`

{ "value": 2.5, "max_volts": 5.0, "enabled": true }

`/response` `DacConfig`

{ "value": 2.5, "max_volts": 5.0, "enabled": true, "error": null }

bang_bang

Bang-bang control loop command and status

Topic Suffix	Dir	Kind	Example JSON
`/config`	in	cmd	`{ "upper_threshold": 50.0, "lower_threshold": 40.0, "update_frequency": 1000, "pause_output": false, "pause_target_in…`
`/response`	out	telemetry	`{ "upper_threshold": 50.0, "lower_threshold": 40.0, "update_frequency": 1000, "pause_output": false, "pause_target_in…`
`/output`	out	telemetry	`{ "output": true, "input": 41.2 }`

Payload Schemas

`/config` `BangBangCommandandResponse`

{ "upper_threshold": 50.0, "lower_threshold": 40.0, "update_frequency": 1000, "pause_output": false, "pause_target_input": false }

`/response` `BangBangCommandandResponse`

{ "upper_threshold": 50.0, "lower_threshold": 40.0, "update_frequency": 1000, "pause_output": false, "pause_target_input": false }

`/output` `BangBangData`

{ "output": true, "input": 41.2 }

bme280

BME280 environmental sensor (temperature, pressure, humidity, dewpoint)

Topic Suffix	Dir	Kind	Example JSON
`/config`	in	cmd	`{ "standby":"62ms", "mode":"Weather", "offset":0.0 }`
`/data`	out	telemetry	`{ "temperature": { "value":23.5, "unit":"C" }, "pressure": { "value":101325, "unit":"Pa" }, "humidity": { "value":45.…`
`/response`	out	telemetry	`{ "temperature": { "value":23.5, "unit":"C" }, "pressure": { "value":101325, "unit":"Pa" }, "humidity": { "value":45.…`

Payload Schemas

`/config` `Bme280Command`

{ "standby":"62ms", "mode":"Weather", "offset":0.0 }

`/data` `Bme280Data`

{ "temperature": { "value":23.5, "unit":"C" }, "pressure": { "value":101325, "unit":"Pa" }, "humidity": { "value":45.2, "unit":"%RH" }, "dewpoint": { "value":11.2, "unit":"C" } }

`/response` `Bme280Data`

{ "temperature": { "value":23.5, "unit":"C" }, "pressure": { "value":101325, "unit":"Pa" }, "humidity": { "value":45.2, "unit":"%RH" }, "dewpoint": { "value":11.2, "unit":"C" } }

command

Send an arbitrary command to another service in-firmware

Topic Suffix	Dir	Kind	Example JSON
``	in	cmd	`{ "data":true }`

Payload Schemas

`` `CommandCmd`

{ "data":true }

complementary_pwm

Complementary PWM output pair with deadtime

Topic Suffix	Dir	Kind	Example JSON
`/config`	in	cmd	`{ "enable":true, "duty":0.4, "frequency":20000, "deadtime":0.02 }`
`/response`	out	telemetry	`{ "enable":true, "duty":0.4, "frequency":20000, "deadtime":0.02, "error":null }`

Payload Schemas

`/config` `ComplementaryPwmCommand`

{ "enable":true, "duty":0.4, "frequency":20000, "deadtime":0.02 }

`/response` `ComplementaryPwmCommandResponse`

{ "enable":true, "duty":0.4, "frequency":20000, "deadtime":0.02, "error":null }

digital_in

Digital input state reporting

Topic Suffix	Dir	Kind	Example JSON
`/out`	out	telemetry	`{ "data": true }`

Payload Schemas

`/out` `DigitalInData`

{ "data": true }

digital_out

Digital output control and feedback

Topic Suffix	Dir	Kind	Example JSON
`/config`	in	cmd	`{ "command": true }`
`/response`	out	telemetry	`{ "data": true }`

Payload Schemas

`/config` `DigitalOutCommand`

{ "command": true }

`/response` `DigitalOutData`

{ "data": true }

flowmeter

Flow meter pulse counting and rate reporting

Topic Suffix	Dir	Kind	Example JSON
`/config`	in	cmd	`{ "slope":1.0, "offset":0.0, "measurement_interval":1000 }`
`/response`	out	telemetry	`{ "slope":1.0, "offset":0.0, "measurement_interval":1000 }`
`/data`	out	telemetry	`{ "value": 3.21, "units": "L/min" }`

Payload Schemas

`/config` `FlowMeterConfig`

{ "slope":1.0, "offset":0.0, "measurement_interval":1000 }

`/response` `FlowMeterConfig`

{ "slope":1.0, "offset":0.0, "measurement_interval":1000 }

`/data` `FlowMeterData`

{ "value": 3.21, "units": "L/min" }

ir_cam

IR camera max pixel and frame row data. One frame consists of 36 rows of 24 pixels.

Topic Suffix	Dir	Kind	Example JSON
`/max`	out	telemetry	`{ "data": 41.7 }`
`/{row}`	out	telemetry	`[23.1, 23.5, 23.6, ... 24 vals]`

Payload Schemas

`/max` `IrCamMaxData`

{ "data": 41.7 }

`/{row}` `IrCamFrameRow`

[23.1, 23.5, 23.6, ... 24 vals]

loadcell

Load cell data (publishes raw/converted weight) and tare command

Topic Suffix	Dir	Kind	Example JSON
``	out	telemetry	`{ "value": 12.34, "unit": "g" }`
`/tare`	in	cmd	`true`

Payload Schemas

`` `LoadCellData`

{ "value": 12.34, "unit": "g" }

`/tare` `LoadCellTareCommand`

true

math

Arbitrary math expression using other services in a firmware. Result will either be f32 or bool depending on the configured output type of the channel.

Topic Suffix	Dir	Kind	Example JSON
`/pause`	in	cmd	`true`
`/ch{0..num_channels}`	in	telemetry	`{"data": 1.0 } or {"data": true }`
`/response`	out	telemetry	`{ "data":true }`

Payload Schemas

`/pause` `MathPauseCommand`

true

`/ch{0..num_channels}` `MathResult`

{"data": 1.0 } or {"data": true }

`/response` `MathPauseResponse`

{ "data":true }

mpu6050

MPU6050 IMU configuration and accel/gyro telemetry

Topic Suffix	Dir	Kind	Example JSON
`/config`	in	cmd	`{ "accel": 2, "gyro": 1 }`
`/accel`	out	telemetry	`{ "x":0.01, "y":-0.02, "z":0.98, "temp":36.5, "roll":1.2, "pitch":-0.7 }`
`/gyro`	out	telemetry	`{ "x":0.1, "y":-0.1, "z":0.05, "temp":36.5 }`
`/response`	out	telemetry	`{ "accel": "2g", "gyro": "250dps" }`

Payload Schemas

`/config` `MpuConfig`

{ "accel": 2, "gyro": 1 }

`/accel` `MpuAccelData`

{ "x":0.01, "y":-0.02, "z":0.98, "temp":36.5, "roll":1.2, "pitch":-0.7 }

`/gyro` `MpuGyroData`

{ "x":0.1, "y":-0.1, "z":0.05, "temp":36.5 }

`/response` `MpuConfigResponse`

{ "accel": "2g", "gyro": "250dps" }

pds

Power distribution system channel & rail configuration and telemetry

Topic Suffix	Dir	Kind	Example JSON
`/config`	in	cmd	`{ "rail":"Vcc2I", "over_current_limit":10, "over_voltage_limit":26, "enable":true }`
`/ch0`	out	telemetry	`{ "state":"Running", "current":0.12, "enabled":true, "power_good":true }`
`/ch1`	out	telemetry	`{ "state":"Running", "current":0.5, "enabled":true, "power_good":true }`
`/ch2`	out	telemetry	`{ "state":"Disabled { rt: None }", "current":0, "enabled":false, "power_good":false }`
`/ch3`	out	telemetry	`{ "state":"Disabled { rt: None }", "current":0, "enabled":false, "power_good":false }`
`/ch4`	out	telemetry	`{ "state":"Disabled { rt: None }", "current":0, "enabled":false, "power_good":false }`
`/ch5`	out	telemetry	`{ "state":"Disabled { rt: None }", "current":0, "enabled":false, "power_good":false }`
`/ch6`	out	telemetry	`{ "state":"Disabled { rt: None }", "current":0, "enabled":false, "power_good":false }`
`/ch7`	out	telemetry	`{ "state":"Disabled { rt: None }", "current":0, "enabled":false, "power_good":false }`
`/vcc1i`	out	telemetry	`{ "state":"Running", "current":0.50, "voltage":5.05, "enabled":true }`
`/vcc2i`	out	telemetry	`{ "state":"Running", "current":0.40, "voltage":12.08, "enabled":true }`

Payload Schemas

`/config` `PowerRailConfig`

{ "rail":"Vcc2I", "over_current_limit":10, "over_voltage_limit":26, "enable":true }

`/ch0` `PowerChannelResponse`

{ "state":"Running", "current":0.12, "enabled":true, "power_good":true }

`/ch1` `PowerChannelResponse`

{ "state":"Running", "current":0.5, "enabled":true, "power_good":true }

`/ch2` `PowerChannelResponse`

{ "state":"Disabled { rt: None }", "current":0, "enabled":false, "power_good":false }

`/ch3` `PowerChannelResponse`

{ "state":"Disabled { rt: None }", "current":0, "enabled":false, "power_good":false }

`/ch4` `PowerChannelResponse`

{ "state":"Disabled { rt: None }", "current":0, "enabled":false, "power_good":false }

`/ch5` `PowerChannelResponse`

{ "state":"Disabled { rt: None }", "current":0, "enabled":false, "power_good":false }

`/ch6` `PowerChannelResponse`

{ "state":"Disabled { rt: None }", "current":0, "enabled":false, "power_good":false }

`/ch7` `PowerChannelResponse`

{ "state":"Disabled { rt: None }", "current":0, "enabled":false, "power_good":false }

`/vcc1i` `PowerRailResponse`

{ "state":"Running", "current":0.50, "voltage":5.05, "enabled":true }

`/vcc2i` `PowerRailResponse`

{ "state":"Running", "current":0.40, "voltage":12.08, "enabled":true }

pid

PID controller command, response, and output topics

Topic Suffix	Dir	Kind	Example JSON
`/config`	in	cmd	`{ "kp":0.2, "ki":0.02, "kd":0.4, "setpoint":1.0, "pause_output":false, "pause_target_input":false }`
`/response`	out	telemetry	`{ "kp":0.2, "ki":0.02, "kd":0.4, "setpoint":1.0, "pause_output":false, "pause_target_input":false }`
`/output`	out	telemetry	`{ "output":0.15, "last_output":0.14, "setpoint":1.0, "input":0.92 }`

Payload Schemas

`/config` `PidCommandAndResponse`

{ "kp":0.2, "ki":0.02, "kd":0.4, "setpoint":1.0, "pause_output":false, "pause_target_input":false }

`/response` `PidCommandAndResponse`

{ "kp":0.2, "ki":0.02, "kd":0.4, "setpoint":1.0, "pause_output":false, "pause_target_input":false }

`/output` `PidData`

{ "output":0.15, "last_output":0.14, "setpoint":1.0, "input":0.92 }

pwm

Standard PWM output control and response

Topic Suffix	Dir	Kind	Example JSON
`/config`	in	cmd	`{ "enable":true, "duty":0.5, "frequency":1000 }`
`/response`	out	telemetry	`{ "enable":true, "duty":0.5, "frequency":1000, "error":null }`

Payload Schemas

`/config` `PWMCommand`

{ "enable":true, "duty":0.5, "frequency":1000 }

`/response` `PWMCommandResponse`

{ "enable":true, "duty":0.5, "frequency":1000, "error":null }

qmc5883l

QMC5883L magnetometer heading / vector data and configuration

Topic Suffix	Dir	Kind	Example JSON
`/config`	in	cmd	`{ "field_range":2, "data_rate":50, "oversample":512, "declination": -13.2 }`
``	out	telemetry	`{ "x": 120.0, "y": -30.5, "z": 5.2, "heading": 182.4 }`
`/response`	out	telemetry	`{ "success": { "field_range":2, "data_rate":50, "oversample":512, "declination": -13.2 }, "error": null }`

Payload Schemas

`/config` `Qmc5883lConfig`

{ "field_range":2, "data_rate":50, "oversample":512, "declination": -13.2 }

`` `Qmc5883lData`

{ "x": 120.0, "y": -30.5, "z": 5.2, "heading": 182.4 }

`/response` `Qmc5883lConfigResponse`

{ "success": { "field_range":2, "data_rate":50, "oversample":512, "declination": -13.2 }, "error": null }

stateful_actuator

Stateful actuator sequences, moves and status topics (schema-defined config)

Topic Suffix	Dir	Kind	Example JSON
`/command`	in	cmd	`{ "command": "TRANSITION"}`
`/fault`	in	cmd	`{ "error": "Invalid State", "inputs": [true,false], "outputs": [true,false], "current_state": "IDLE" }`
`/sequence`	out	telemetry	`{ "name": "seq1", "success": true }`
`/state`	out	telemetry	`{ "success": true, "inputs": [true,false], "outputs": [true,false], "current_state": "IDLE" }`

Payload Schemas

`/command` `StatefulActuatorCommand`

{ "command": "TRANSITION"}

`/fault` `StatefulActuatorFault`

{ "error": "Invalid State", "inputs": [true,false], "outputs": [true,false], "current_state": "IDLE" }

`/sequence` `StatefulActuatorSequenceStatus`

{ "name": "seq1", "success": true }

`/state` `StatefulActuatorState`

{ "success": true, "inputs": [true,false], "outputs": [true,false], "current_state": "IDLE" }

stepper

Stepper driver motion command, response and status progress

Topic Suffix	Dir	Kind	Example JSON
`/config`	in	cmd	`{ "target_accel":0.1, "max_velocity":0.5, "num_steps":2000, "direction":true, "enable":true }`
`/response`	out	telemetry	`{ "target_accel":0.1, "max_velocity":0.5, "num_steps":2000, "direction":true, "enable":true }`
`/status`	out	telemetry	`{ "percent": 42, "steps": 840, "position": 1234 }`

Payload Schemas

`/config` `StepperConfig`

{ "target_accel":0.1, "max_velocity":0.5, "num_steps":2000, "direction":true, "enable":true }

`/response` `StepperConfig`

{ "target_accel":0.1, "max_velocity":0.5, "num_steps":2000, "direction":true, "enable":true }

`/status` `StepperStatus`

{ "percent": 42, "steps": 840, "position": 1234 }

thermocouple

Thermocouple temperature readings

Topic Suffix	Dir	Kind	Example JSON
`/temperature`	out	telemetry	`{ "temperature": 23.5, "ambient": 22.1, "unit": "C", "error": null }`

Payload Schemas

`/temperature` `ThermocoupleData`

{ "temperature": 23.5, "ambient": 22.1, "unit": "C", "error": null }