Set Lifetime Command - Globalstar ST100 User Manual

8545-0194-01 v1.0
4.2.2.25. "Set Lifetime" command
This command sets the lifetime of the device. Upon getting its first GPS fix after the "set lifetime" command is issued, the
device will calculate an end of life date based on the value sent in this command.
BYTE BITS
0 0 - 7
1 0 - 7
2 0 - 7
3 0 - 7
4-5 0 - 15
This response is sent in response to a "Set Lifetime" command.
BYTE BITS
0 0 - 7
1 0 - 7
2 0 - 7
3-4 0 - 15
The first time the unit gets a GPS fix after this command is issued, an end date will be calculated.
The factory default lifetime is 1 month. If this command is never issued, the unit will expire 1 month after getting its first GPS
fix. Until it has gotten that first fix and calculated its expiration date, any command that would cause it to transmit without first
obtaining a GPS fix will be NAK'd.
A value of 0 is a special case and will cause "today" to be the end date. The device lifetime will expire, and it will cease to
operate at midnight GMT on the day that it gets its first fix after this command is issued.
If the value is nonzero, the first time the unit gets a GPS fix after this command is issued it will calculate an end date, its final
date of operation, that is on this day of the month, that many months hence.
If the "expiration month" has fewer days than the day it got its fix (e.g. it got its first fix on the 31st of the month and the
expiration month has 30 days) the last day of the expiration month will be its last day of operation.
Once the unit has "expired", it will not engage its satellite transmitter, and any command that would result in one or more
satellite transmissions will be NAK'd. It will drop out of track mode if in track mode. Simple query commands (e. g. querying for
its ESN or firmware versions) will still work.
Examples:
• Lifetime is set for 12 months and unit gets its first fix after setting the lifetime on Jan. 21, 2020: Last day of operation will be
Jan 21, 2021. Beginning Jan. 22, 2021, the unit will be shutdown.
• Lifetime is set for 18 months and unit gets its first fix after setting the lifetime on Mar. 31, 2020: Last day of operation will be
Sep. 30, 2021. Beginning Oct. 1, 2021, unit will be shut down.
ST100 User Manual v1

SET LIFETIME COMMAND

PARAMETER
Leader
Length
Command Code
Time to live, expressed in Months
CRC
PARAMETER
Leader
Length
Command Code
CRC
Confidential & Proprietary Information
DESCRIPTION
Always a value of 0xAA
0x70 = Set Lifetime Command
Valid values are the entire span of the byte minus 1. 0 to 254 months. See
description below for how the end date is calculated and interpreted.
DESCRIPTION
Always a value of 0xAA
0x05
0x70 = "Set Lifetime"
Will contain the response CRC
0x06
48