Type 1 Message Class; Truncated Message - Globalstar SmartOne Series User Manual

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Type 1 Message Class

Truncated message type – Single Packet Version (Supported in
firmware version 2.0 and later.)
This message type provides for up to 2 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. The
Truncated message will follow the following on-air format:
Variable
Status Byte
Latitude/Longitude
User Data
Truncated message type – Multiple Packet Version (Supported in
firmware version 2.1 and later.)
The Globalstar simplex messaging protocol provides for single and multiple packet
messaging. In the event that the user application requests a user data length exceeding 9
bytes, the SmartOne (running firmware version 2.1 or later) will automatically
"packetize" the message, that is, transmit it as multiple 9 byte packets. The ground
station appliqué will reverse the process, "de-packetizing" the message back into a single
("long") message. From the user application point of view, this eliminates the 9 byte
limitation allowing the user to compose longer messages transparently. They are
SmartOne Manual Rev 1.5
Motion
Fix Confidence
Bit.
Table 7 - Re-center Message
Bits
8
48
16
the fix.) Value 0 = GPS data
reported is from a 3D fix.
Bit (6) – Value 1 = Device was
In-Motion when the message was
1 transmitted.
was At-Rest when the message
was transmitted.
Bit (7) 0=High confidence in
1 GPS fix accuracy, 1=Reduced
confidence in GPS fix accuracy.
Description
Bit (1:0) = 1 = Truncated message type:
Bit (7:2) = submask data from Truncated user data
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
Byte 1 = User data byte 1
Byte 2 = User data byte 2
DOC# 9100-0268-01
Value 0 = Device
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