Ringer Wire
Open School Bell can use the GPIO pins on a Raspberry Pi connected to a relay to operate ringer wire bell systems. This essentially means that if you have a switch to ring your bells OSB can connect into that and ring the bells for you.
You can find the GPIO Pin Number for the controller using
cat /sys/kernel/debug/gpio
. If using GPIO17 on a Pi5 the pin number is 588,gpio-588 (GPIO17 )