AlarmDecoder pHat

AD2pHAT Bottom
The new AD2pHAT is the latest revision of the AlarmDecoder embedded project. In 2019 it will be replacing the original AD2Pi that was introduced in 2013. The original AD2Pi was designed prior to any standards for add-on boards to the Raspberry Pi. Over the past few years the Pi HAT and pHAT form factor were introduced and many add-on designs have migrated to these layouts. The AD2pHAT is using the the pHAT form factor 30mm x 65mm. This more compact form factor works better with the Pi Zero and still works on the full sized Pi. It is also smaller and closer in size to other micro controllers such as the ESP32Thing that with an adapter[1] can be used instead of a Pi as the host controller.

This new design includes several new features.
  • The ability to monitor the AD2 Heartbeat signal via GPIO23.
  • The ability to physically reboot the AD2 embedded device via GPIO18.
  • i2c 32kbit Serial EEPROM 24AA32AT-I/OT accessible by the embedded host for device tree configuration via GPIO0(SDA0) and GPIO1(SCL0).
  • Flexible power options.

  1. AD2PiHAT Pin
  2. Estimate. Needs load testing.
  3. Estimate. Needs load testing.