Heartbeat

This page documents the heartbeat configuration

Configuration file fields

This section is autogenerated from the Rule Schema file.

State can.heartbeat.state

Enable to periodically transmit heartbeat signal.

Type

Default

Options

integer

0

Disable: 0 Enable: 1

ID Format can.heartbeat.id_format

ID format of heartbeat message.

Type

Default

Options

integer

1

Standard (11-bit): 0 Extended (29-bit): 1

ID (hex) can.heartbeat.id

ID of heartbeat message in hex. Example: 1FF.

Type

Default

string

00435353

Configuration explained

This section contains additional information and examples.

Note

The heartbeat cannot be disabled using the control signal

Note

The heartbeat feature requires a CAN-bus physical mode supporting transmissions

Payload format

The device can transmit a 1 Hz periodic heartbeat signal. The signal payload contains logging state (enabled/disabled), the device time and space left on the SD-card in MB.

The interpretation of the 8-byte data payload of the heartbeat signal is given below:

Byte No.

0

1

2-5

6-7

Interpretation

Fixed 0xAA

State

Epoch time

Space left

  • Byte 0 has the reserved value 0xAA

  • The Epoch time is time-zone and offset adjusted

  • Multi-byte fields should be interpreted MSB (Most-SignificantByte) first

  • The State holds information on the current rx_state / tx_state:

    • 0: RX disabled, TX disabled

    • 1: RX enabled, TX disabled

    • 2: RX disabled, TX enabled

    • 3: RX enabled, TX enabled

Heartbeat with payload: AA 03 5D 78 FB 8B 1D 93

Byte No.

0

1

2-5

6-7

Interpretation

Fixed

State

Epoch time

Space left

Payload

0xAA

0x03

0x5D78FB8B

0x1D93

  • Fixed: 0xAA

  • State: RX and TX enabled

  • Epoch time: \(\text{5D78FB8B}_{16} = 1568209803_{10}\) -> 11/09/2019 13:50:03

  • Space left: \(\text{1D93}_{16} = 7571_{10}\text{ MB}\)

Heartbeat with payload: AA 00 5D 78 FB 8B 00 00

Byte No.

0

1

2-5

6-7

Interpretation

Fixed

State

Epoch time

Space left

Payload

0xAA

0x00

0x5D78FB8B

0x0000

  • Fixed: 0xAA

  • State: RX and TX disabled

  • Epoch time: \(\text{5D78FB8B}_{16} = 1568209803_{10}\) -> 11/09/2019 13:50:03

  • Space left: \(\text{0000}_{16} = 0_{10}\text{ MB}\)