Protocol Spec¶

This document outlines the control and data collection protocol used to send and receive data from the laser microcontroller.

Format of this document¶

Most packets are represented using [name:type] syntax.

Some types are as follows:

• u{n}: an unsigned {n} bit integer in little endian format. (ex. u8)
• i{n}: a signed {n} bit integer in little endian format. (ex. i8)
• [{len}]{type}: an array of {type} with length {len} (ex. [10]u8)

General Message Format¶

[type:u8][subtype:u8][len:u32][content]

Data commands (type=0)¶

DATA_UPTIME (type=0,subtype=0)¶

A regular status heartbeat (sent every ~0.5s)

[uptime:u32][lasterror:u16]

DATA_LOG (type=0,subtype=1)¶

Some logging information from the firmware.

[level:u8][...message:bytes]

DATA_SENSOR (type=0,subtype=2)¶

Sensor data

[id:u8][value:f32]

COMMAND commands (type=½)¶

GET_INFO (type=1,subtype=0)¶

Gets the current status from the Arduino. (No arguments)

RET_INFO (type=2,subtype=0)¶

Sends the status back to the computer.

[uuid:[36]u8]         // As a fixed length string
[version:u16]
[build_date:[11]u8]   // In the format: Mmm dd yyyy
[build_time:[8]u8]    // In the format: hh:mm:ss

LASER_POWER (type=1,subtype=2)¶

Sets a pin high or low

[pin:u8]
[out:u8]    // 1 for high 0 for low

RET_LASER_POWER (type=1,subtype=2)¶

no data