Globalstar SmartOne - Manual (Page 59)

SmartOne Manual Rev 1.4 DOC# 9100-0268-01 p.59
presented to the user by the Globalstar back office as complete messages of a length
longer than 9 bytes. The SmartOne supports user-defined messages (Class 1 and 2) of up
to 54 bytes.
This message type provides for up to 47 bytes plus 6 bits of user data to be appended to
the status byte and GPS location information. The input and status bits data of the
standard message are replaced with user data from the serial configuration port. Note:
Total message length will be a minimum of 9 bytes in length, and a maximum of 54 bytes
in length, and the length sent to the user will always be divisible by 9. The Truncated
message will follow the following on-air format:
Variable Bits Description
Status Byte 8 Bit (1:0) = 1 = Truncated message type:
Bit (7:2) = submask data from Truncated user data
Latitude/Longitude 48 Byte 1 = Latitude MSByte
Byte 2 = Latitude
Byte 3 = Latitude LSByte
Byte 4 = Longitude MSByte
Byte 5 = Longitude
Byte 6 = Longitude LSByte
360 degrees of longitude coded in signed binary with 3
bytes and 180 degrees of latitude coded in signed binary
with 3 bytes.
Positive longitude correspond to East Longitudes
Positive Latitude correspond to North Latitudes
User Data variable Byte 1 = User data byte 1
Byte 2 = User data byte 2
Byte 3 = User data byte 3
.
.
.
Byte 47 = User data byte 47
Type 2 Message Class
Raw message type – Single Packet Version (Supported in firmware
version 2.0 and later.)
Message type 2 shall be a Raw Payload message. This message type provides for up to 8
bytes plus 6 bits of user data. This mode is provided to enable the user to directly send a
single data burst through the network. The only bits not accessible to the user are the
message type bits needed by the receiving data processor to delineate message type
associated to the TXID. User data less than the full payload will be zero padded as
necessary. The Raw Payload message will follow the following on-air format:
Variable Bits Description
Status Byte 8 Bit (1:0) = 2 = Raw Payload message type:
Bit (7:2) = submask data from Raw Payload user data
User Data 64 Byte 1 = User data byte 1
Byte 2 = User data byte 2
Byte 3 = User data byte 3
Byte 4 = User data byte 4