Driver FT5206

Introduction

FILES: Source, Header

The FT5206 driver is to manage the capacitive touch interface of the LCD. A datasheet for the FT5206 IC can be found here. It uses I2C for communication and when it's mounted on the LCD used in this project it has an address of 0x38.

Touch events

There are three different touch events that can happen.

• Put Down - The first time a finger is put down on the screen
• Contact - Keeps happening as long as a finger is in contact with the display
• Put Up - When a finger leaves the screen after there's been contact

Data acquisition

To make things as simple as possible the FT5206 is setup to generate an interrupt with a set frequency every time there is a touch event. When the interrupt is triggered the MCU request the touch data from the FT5206 to determine what kind of event it was and where it happened. This data is then forwarded to the LCD task using a LCD Task Message.

Multiple finger support

There is support for up to five simultaneous fingers where each finger will be tracked individually by the FT5206. This is currently not being used in this project but might be useful in the future.