Protocol Specification

Message Format (31 bytes) 

┌──────────┬─────────────┬──────────────────┬──────────┐
│  typeID  │ commandType │     data[7]      │   crc8   │
│ (1 byte) │  (1 byte)   │   (28 bytes)     │ (1 byte) │
└──────────┴─────────────┴──────────────────┴──────────┘
Field Size Description
typeID 1 byte Module type (sensor=1, motor=2, etc.)
commandType 1 byte Command (read=0, set=1, reset=2, etc.)
data[7] 28 bytes Payload data (7 floats)
crc8 1 byte CRC-8 over typeID, commandType, data[7]

Notes:

  • sliceAddress exists in the struct but is not serialized.
  • CRC excludes sliceAddress and the CRC byte itself.

Communication Patterns 

Controller [31-byte message]> Peripheral    # Send command
Controller [I2C request]> Peripheral        # Request data
Controller <[31-byte response] Peripheral   # Response

Standard Values

Module Types

  • 0: Generic
  • 1: Sensor
  • 2: Actuator
  • 3: Display
  • 4: Input

Command Types

  • 0: Read data
  • 1: Set parameters
  • 2: Reset
  • 3: Calibrate

CRC

  • Polynomial: 0x07 (CRC-8)
  • Calculated using ace_crc::crc8_nibble
  • Applied to serialized payload before padding

Timing Guidelines

  • 10ms minimum between messages
  • 50ms timeout for peripheral response
  • 100kHz I2C clock speed (standard)
  • Addresses 0x08-0x77 usable