Datasheet

20 34 12 01 FF
The first byte is the Message Type (0x20), which identifies this as a response message.
The second and third bytes are 0x1234, which is the unique command ID that this response is related to.
The fourth byte indicates that we have a message payload of 1 byte.
The fifth byte is the 1 byte payload: 0xFF
Alert Messages
Alert messages (Message Type = 0x40) are sent whenever an alert condition is present on the system (low battery,
etc.), and have the following structure:
A sample alert message would be:
40 CD AB 04 42 07 00 10
The first byte is the Message Type (0x40), which identifies this as an alert message.
The second and third bytes are 0xABCD, which is the unique alert ID.
The fourth byte indicates that we have a message payload of 4 bytes.
The last four bytes are the actual payload: 0x10000742 in this case, assuming we were transmitting a 32-bit
value in little-endian format.
Standard Alert IDs
0: Message Type (U8)
1+2: Command ID (U16)
3: Payload Len (U8)
4: Payload
0x20
0x34 0x12
0x01
0xFF
Name
Message Type
Alert ID
Payload Length
Payload
Type
U8
U16
U8
...
Meaning
Always '0x40'
Unique ID for the Alert Condition
Payload Length (0..16)
Optional response payload
0: Message Type (U8)
1+2: Alert ID (U16)
3: Payload Length
4+5+6+7: Payload
0x40
0xCD 0xAB
0x04
0x42 0x07 0x00 0x10
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