Capacitive Touchscreen Paint Demo

This page is for the Capacitive Touch Screen version of the Shield!

We now have a super-fancy capacitive touch screen version of this shield. Instead of a resistive controller that needs calibration and pressing down, the capacitive has a hard glass cover and can be used with a gentle fingertip. It is a single-touch capacitive screen only!

The capacitive touch screen controller communicates over I2C, which uses two hardwire pins. However, you can share these pins with other sensors and displays as long as they don't conflict with I2C address 0x38.

Download the FT6206 Library

To control the touchscreen you'll need one more library - the FT6206 controller library which does all the low level chatting with the FT6206 driver chip. Use the library manager and search for FT6206 and select the Adafruit FT6206 library:

Once you have the library installed, restart the IDE. Now from the examples->Adafruit_FT6206 menu select CapTouchPaint and upload it to your Arduino.
The touch screen is made of a thin glass sheet, and its very fragile - a small crack or break will make the entire touch screen unusable. Don't drop or roughly handle the TFT and be especially careful of the corners and edges. When pressing on the touchscreen, remember you cannot use a fingernail, it must be a fingerpad. Do not press harder and harder until the screen cracks!

FT6206 Library Reference

Getting data from the touchscreen is fairly straight forward. Start by creating the touchscreen object with
Adafruit_FT6206 ts = Adafruit_FT6206();
We're using hardware I2C which is fixed in hardware so no pins are defined.
Then you can start the touchscreen with
ts.begin()
Check to make sure this returns a True value, which means the driver was found. You can also call begin(threshvalue) wish a number from 0-255 to set the touch threshhold. The default works pretty well but if you're having too much sensitivity (or not enought) you can try tweaking it

Now you can call
if (ts.touched())
to check if the display is being touched, if so call:
TS_Point p = ts.getPoint();
To get the touch point from the controller. TS_Point has .x and .y data points. The x and y points range from 0 to 240 and 0 to 320 respectively. This corresponds to each pixel on the display. The FT6206 does not need to be 'calibrated' but it also doesn't know about rotation. So if you want to rotate the screen you'll need to manually rotate the x/y points!
Last updated on 2018-01-13 at 08.52.27 PM Published on 2014-01-03 at 12.34.44 PM