1.4.1.1 Communication Protocol

This section details the different frames used in the Host Interface.

Frame Types

Command Frame

Byte Index0123 : (Len + 3)(Len+4) : (Len+5)
FieldFSLenCMDPayloadBYTE Checksum
  • FS (Frame Start):
    • 0x02: First TX packet
    • 0x03: Retransmission
  • Len: Number of bytes of the Payload - 1
    • 0...255
  • Payload: Depend on the type of command
  • BYTE Checksum computed on Len, Cmd and Payload

By default, all multi-byte fields are transmitted following little endian order (less significant byte is transmitted first).

ACK Frame

Byte Index0
ACK0x06
NACK0x15

Status Message

Byte Index0123
FieldMsg StartStatusStatus Mask
  • Msg Start: 0x3F
  • Status:
    b7b6b5b4b3b2b1b0
    RSV3RSV2RSV1Plc BusyRxTxSet
    • Set:
      • 0: Device has an internal configuration issue
      • 1: Device is configured and running properly
    • Tx:
      • 0: No TX is in progress
      • 1: TX is in progress
    • Rx:
      • 0: No RX is in progress
      • 1: RX is in progress
    • Plc Busy:
      • 0: PHY layer is idle
      • 1: PHY layer is busy or not configured
  • Status Mask:
    • Each bit maps the configuration status of a MIB object. The bit index is defined in Management Information Base (MIB).
      • 0: Object is correctly configured
      • 1: Object is at default value
    b15b14b13b12b11b10b9b8b7b6b5b4b3b2b1b0
    ---Timing----ACA

    Mnf

    data

    		-FW Rel.MAC cfg---

UART Arbitration

  • Device → Host Controller (HC):
    • Device can send a frame asynchronously to the HC
  • Host Controller (HC) → Device:
    1. HC must first send a request (T_REQ signal)
    2. The Device shall allow the HC to communicate by sending a status message frame