Introduction

The GPIO bus model is one of the standard bus models available in TEMU. The bus model maintains the values of 64 GPIO pins, and a notification list where pin updates can be forwarded to an arbitrary number of models when pin values have changed.

This does place a limitation, in that a model must know which pin it is connected to, which may not be ideal. The recommended approach is to ensure that the model maintains its own user configurable mask for filtering out the relevant bits.