NavCom Sapphire Rev.J - Manual (Page 225)

Sapphire Technical Reference Manual Rev. J
225
1.181 SHUTDOWN (ASCII)
SF-3050 Sapphire SF-3040
This command shuts down the Sapphire and Power I/O boards.
Command: [SHUTDOWN] {action} {delay}
Parameter Definition
Action
keywords (HALT, REBOOT). HALT tells the system to execute an orderly shutdown
and to power down the system. REBOOT tells the system to execute an orderly
shutdown and reboot.
Delay
A value in seconds defining how long to wait before shutting down (default = 0
seconds)

If no arguments are entered, the command is treated as a query and will respond
with the most recent action request and remaining time until it is implemented.

The response to the [SHUTDOWN] command depends on how the unit is powered,
rather than on the HALT or REBOOT keywords. If it is powered from the front panel
ON/OFF switch, the unit always halts (powers down). If it is powered from the
ignition pin, it always reboots (powers up).

Logic is implemented to detect if the receiver shut down gracefully. The GNSS
board monitors the PIO heartbeat message age. When the GNSS board receives a
shutdown command, it saves this PIO heartbeat message age as a missing
heartbeat count in NVRAM.
When the receiver is powered on, the GNSS board retrieves the missing heartbeat count from
NVRAM and sends it to the PowerIO board. Once the GNSS board sends this missing
heartbeat count to the PowerIO board, it invalidates this missing heartbeat count to (-2) and
saves it in NVRAM.
When the receiver is powered on, if the GNSS board is unable to retrieve the missing heartbeat
count from NVRAM, the GNSS sends an invalid missing heartbeat count (-1) to the PowerIO
board. Once the GNSS board sends this missing heartbeat count to the PowerIO board, it
invalidates this missing heartbeat count to (-2) and saves it in NVRAM.
When the PIO heartbeat message is greater than 1 and is modulo 60, the GNSS automatically
saves it as a missing heartbeat count in NVRAM. Values that may be written in NVRAM are 60,
120, 180, and 240.
Based on this missing heartbeat count, the PowerIO determines whether the receiver
experienced an ungraceful shutdown.
If the missing heartbeat count is equal to or greater than 0 and less than 60, the receiver
experienced a previous graceful shutdown.
If the missing heartbeat count is equal to or greater than 60, the receiver experienced a
previous ungraceful shutdown, and the following message is output:
[PANICA]0,0.0,0, PREVIOUSLY UNGRACEFUL SHUTDOWN IS DETECTED: code (12)
Code 12 indicates that this ungraceful shutdown was triggered by the watchdog time reset on
the PowerIO board.