Wireless Sensor Network Solution ANT Message Protocol 박 유 진

Introduction 2.4 GHz bidirectional wireless Personal Area Network Communication Technology low latency Ultra-low power consumption(Can use coin battery)

Network Topology

ANT Nodes Each node in an ANT network consists of an ANT protocol engine and a host controller(MCU)

ANT Channel A Channel must be established to connect two nodes together A Channel consist of :

ANT Channel Configuration Network Number & Network Key RF Frequency Channel ID Transmission Type Device Type & Device Number Channel Type Channel Period Data Type & Data Format

Network Network Number(8 bit) & Network Key(8 byte) ▫Define Network and Access(Security Option) RF Frequency ▫8 bit field with acceptable values range from 0 to 124(2400MHz ~ 2525MHz) ▫ex) 2466MHz ~ 2467MHz = RF frequency value 66

Channel Identification Transmission Type(8 bit) ▫Define Share Channel or Other Transmission Characteristics of a Device Device Type(8 bit) ▫Differentiate between Device of Network Device Number(16bit) ▫Unique Number for a given device type

Channel Type Specify the type of communication that will occur on the channel ValueDescription 0x00Bidirectional Receive Channel 0x10Bidirectional Transmit Channel 0x20Shared Bidirectional Receive Channel 0x30Shared Bidirectional Transmit Channel 0x40Receive Channel with option to not clear wild card upon successful match 0x50Transmit Only Channel

Channel Period ▫Basic message rate of data packet sent by the master Data Types & Data Format ▫Channel data type determine the type of communication data - Broadcast data - Acknowledge data - Burst data

Forward Channel Communication Master → Slave Broadcast Data ▫The most basic data type(system default) ▫The least amount of RF bandwidth and system power consumption ▫One – way transmission(no acknowledge) ▫Send at every time slot of message period ▫If no new data, previous message is re-transmitted

Acknowledged Data ▫At any time during an established use two-way connection, the master can choose to send an acknowledged data packet in place of a broadcast data packet ▫But no automatic re-transmission of unacknowledged data packets Burst Data ▫Burst data transmission provides a mechanism for the master to send large amounts of data to the slave ▫Any lost messages are automatically re-transmitted

Reverse Channel Data Broadcast Data ▫Broadcast message are sent only once on the reverse channel Acknowledged Data ▫At any time during an established two-way connection, the slave can optionally choose to send an acknowledged data packet to the master at the end of a Channel timeslot Burst Data ▫Burst Data transmit from slave to master at the end of a Channel timeslot.

Independent & Shared Channel Independent Channel ▫Connection of only one master and one slave Shared Channel ▫Use two byte Shared Channel Address ▫A Shared Channel can support more than slave device using a single independent channel ▫The master can send data to all slaves at the same time using the Shared Channel Address 0

Establishing Channel 1.The master select its network type, frequency, and message rate 2.The master establishes the channel by transmitting 8-byte payload packet in a particular timeslot at the established message rate 3.The slave selects the network type, frequency, and message rate 4.The slave establishes a new ANT channel by searching for the intended unique master 5.Once the master has been located, a connection is established, and the slave receives data indefinitely from the master at the given timeslot and message rate.

Independent Channel(Example) Node B is to use the broadcast data type Node D is to use the broadcast data type Node C requires the acknowledged data type

Channel between Node B and Node A where Node B will be the master :

Channel between Node C and Node A where Node C will be the master :

Q & A