Raw Message Type - Multiple Packet Version - Globalstar SmartOne Solar User Manual

9100-0425-01
Raw Message Type – Multiple Packet Version
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 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 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.
Message type 2 shall be a Raw Payload message. This message type provides for up to 53 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 transmit ID. User data less than the full
payload will be zero padded as necessary. 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 Raw Payload message Multiple Packet version will follow the following on-air format:
Variable
Status Byte
User Data
SmartOne Solar™ User Guide v1.0.3
Bits Description
Bit (1:0) = 2 = Raw message type
8
Bit (7:2) = submask data from Raw Payload user data
Byte 1 = User data byte 1
Byte 2 = User data byte 2
Byte 3 = User data byte 3
Variable
.....
.....
Byte 53 = User data byte 53
Confidential & Proprietary Information
16