Telit Wireless Solutions LE51-868S DemoUnit, User Manual

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FIELD LENGTH
(bytes) Possible values Comments
Header 1 0xA5
Length 1 0x00 – 0xFF
It’s the payload length
Type 1 DATA - 0x01
KEEP - 0x02
BIT - 0x03
CONFIRM - 0x10
DATA: simple data
KEEP: used to send a keep
alive message as described
in the SIGFOX standard; it’s
in charge to the user to send
the keep alive message
every 24 hours
BIT: send a status bit
following
the SIGFOX
protocol
Sequence Number 1 0x01 – 0xFF
It’s in charge to user to put a
valid value to recognize the
association packet send –
confirm received
Payload 0x00 – 0xFF Up to customer DATA: up to 255 bytes
KEEP: must be omitted
BIT: one byte with value 0
or 1
CRC 2 Up to customer
It’s the sum of all bytes
except header and tailer (lsb
first)
Tailer 1 0x5A
After receiving a packet on the serial, the firmware sends a confirm packet on the serial port
to inform the user about success or packet error.
The confirm format is the same shown above, and the fields will be filled as follow:
Length
: it’s the payload length, usually 1
Type : it is the same type sent by the host ORed with CONFIRM value.
Sequence number
: it’s the same sent by the host
Payload : is the error code returned by the firmware
enum Ack
{
NO_ERROR = 0,
SERIAL_LENGTH_ERROR,