Atmel MXT336T touch screen with GInput

[krisPainkiller]

Hi, 

I have an Atmel MXT336T touch screen controller (I2C interface type) and I would use it with GInput.

I'm working on a ATSama5D2-XPLAINED-ULTRA and I'm using ChibiOS.

There is any implementation of this touch screen controller on GInput?

And if not, how can I implement it? There is any supported controller driver that I can use as "template"?

Thanks for the help!

[Joel Bodenmann]

Hello and welcome to the µGFX community!

Unfortunately, there isn't an existing GINPUT driver for that touch screen controller. However, it's very easy to add a new one. Take the existing drivers as an example. You can simply copy the one who matches your controller the best (eg. don't take the ones which use the microcontroller's ADC to determine the touch coordinates) and modify from there.
The entire driver interface is well documented in the corresponding GINPUT documentation.

Please don't hesitate to ask if you have any questions - we're happy to help wherever we can!

[krisPainkiller]

Hi Joel and thanks for the answer!

I've currently implemented my touch screen controller in GINPUT and now I want to test it out.

There are some kind of demos in uGfx? Or even better witch function I have to use to test my driver?

My goal is to read row x and y values from the touch screen using uGfx.

Thanks for the help!

[Joel Bodenmann]

Have a look at the /demos directory. Especially /demos/tools in your case.

[krisPainkiller]

Hi,

I've tested the touch_raw_reading demo and works fine. The reading are very responsive though not much accurate on the four angles of my touch screen.

I've also tested the touch_driver_test demo using its tunings and calibrations but the readings aren't responsive at all. It is very difficult to calibrate the touch screen with this demo for me.

There are some configuration in GInput to solve this problem?

[Joel Bodenmann]

1 hour ago, krisPainkiller said:

The reading are very responsive though not much accurate on the four angles of my touch screen.

https://wiki.ugfx.io/index.php/Touchscreen_Calibration#Extreme_coordinates

 

1 hour ago, krisPainkiller said:

I've also tested the touch_driver_test demo using its tunings and calibrations but the readings aren't responsive at all. It is very difficult to calibrate the touch screen with this demo for me.

What do you mean by "not very responsive"? What's the behavior in a regular GWIN application like?