Buzzer
Strato Pi CAN has an on-board buzzer that can be controlled using GPIO20. Simply set
GPIO20 to high to emit a continuous sound, and back to low to stop. The buzzer is not
intended to emit sound indefinitely and could be damaged doing so.
The Strato Pi utility has several commands to control the buzzer.
Buzzer on continuously:
$
sudo strato beep on
Buzzer off:
$
sudo strato beep off
Buzzer on for 500 milliseconds:
$
sudo strato beep 500
Buzzer on for 500 milliseconds, followed by 100 milliseconds pause, repeated three times:
$
sudo strato beep 500 100 3
Relay
Strato Pi CAN has an on-board relay that can be controlled using GPIO26. Simply set
GPIO26 to high to close the NO contact, and to low to open it.
The Strato Pi CAN utility implements a command to control the relay.
Relay on:
$
sudo strato relay on
Relay off:
$
sudo strato relay off
Hardware watchdog
Strato Pi CAN implements a dedicated hardware watchdog circuit that can be used to
perform a full power cycle of the Raspberry Pi.
Being controlled by Raspberry Pi’s GPIO pins, it is extremely easy to control watchdog
operation using simple custom scripts in your application.
The watchdog is normally disabled. To enable it, set GPIO6 pin to high. While GPIO6 is
high, the Strato Pi CAN micro-controller will watch for state changes of the GPIO5
heartbeat pin. You should ensure that GPIO5 flips its state between high and low faster
than every 60 seconds.
If the Strato Pi CAN micro-controller doesn’t see GPIO5 changing state for more than 60
seconds, it will initiate a shutdown procedure, rising the GPIO12 timeout pin to high, to
signal your code that a watchdog timeout has occurred.
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Strato Pi CAN User Guide