Enable the watchdog:
$
sudo strato watchdog enable
Disable the watchdog:
$
sudo strato watchdog disable
Send the heartbeat:
$
sudo strato watchdog heartbeat
Print “1” if the watchdog timeout is expired, “0” if not:
$
sudo strato watchdog timeout; echo $?
Power cycle
You can start a delayed power cycle by rising Raspberry Pi’s GPIO16 pin.
When GPIO16 is set to high, Strato Pi Base will wait 60 seconds and then power off the Pi
board for 5 seconds.
The power cycle also affects the VSOUT auxiliary power supply output.
To initiate a delayed power off cycle:
$
sudo strato shutdown
Advanced configuration
The Strato Pi Base logic controller can be configured from the Raspberry Pi to change the
default behavior and timing of the hardware watchdog. The RX/TX switching mode (TX-
Enable control) of the RS-485 serial port is also configurable.
These configuration parameters can be accessed using the Strato Pi kernel module or
implementing the underlying ASCII-based serial protocol described in the "Strato Pi Logic
Controller Advanced Configuration Guide" document.
Thermal considerations for Strato Pi Base server
The Raspberry Pi draws power and generates heat proportionally to CPU and GPU load.
The Strato Pi main regulator also generates heat proportionally to the total amount of
current that it has to supply to the Raspberry and, if present, external devices.
The thermal behaviour of Strato Pi Base server is dynamic and affected by operating
conditions and the external environment temperature.
The Raspberry Pi CPU has the ability to throttle down its clock speed once a certain core
temperature is reached. This prevents CPU overheating, also limiting the temperature
inside the enclosure, when the CPU load is high for a significant amount of time.
The following charts show the thermal behaviour of Strato Pi Base server in different
conditions, in a typical installation with the device under test installed in a standard, not
ventilated DIN cabinet:
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Strato Pi Base User Guide
