tillitis-key/hw/application_fpga/core/touch_sense

touch_sense

Core that handles touch senor events and provides them SW via an API.

Introduction

This core implements a touch sensor handler. The core detects and holds events for SW to read. The touch sensor input is expected to be a change in level from low (0) to high (1). When an event is seen, the core will set a status bit that SW can read. SW must then clear the event by writing to the status register.

The user is expected to lift the finger between multiple touch events.

API

The API has a single address, and a single bit in that address:

	ADDR_STATUS: 0x09
	STATUS_EVENT_BIT: 0

SW should clear any stray attempts before signalling to the user that a touch event is expected. Clearing an event is done by writing the the status address, the value written does not matter.