Matrix Orbital Corp

How I can to calibrate the touch screen of EVE2-38G on arduino environment?

Hi TFTLCDCyg,

Welcome to the forums!

The EVE2-38G uses a FocalTech GT911 touch controller and in order to enable and calibrate the EVE2-38G's capacitive touch panel, you will need to upload a touch configuration file to the EVE2's FT813 chip.This is detailed further in sections 6.6.2 and 6.6.3 of FTDI's Selecting an LCD Display application note published on their website here :

https://brtchip.com/wp-content/uploads/ ... isplay.pdf

The configuration file is considerably large, and will take up a large amount of code space in the Arduino's memory, so it is recommended that you purchase a shield, like our EVE2-SHIELD, with SD card support. You will be able to store the touch configuration file on the SD card, and upload it to the FT813 upon startup, freeing up a lot of Arduino code space.

We will be releasing the EVE2's successor, the EVE3, in the near future. The EVE3 will use FTDI/Bridgtek's new BT815 chip, which will come pre-loaded with the touch configuration file. The BT815 will eliminate the need for uploading the large configuration file, and will reduce the touch setup process down to one register change.

Hopefully this answers your question. If you would like a code example, please let me know.

Cheers,
Daniel

Dear sir,
I also struggle to bring my cofig into function. I try to use the arduino "EveSchool" project with an arduino uno, an EVE2-SHIELD and an EVE2-50G- capacitive touch screen. What i already tried to do is to change the lib from resistive to capacitive touch screen. The display shows all the different screens but the touch will not work at all. What i have tried to do is to sent the additional touch config while the ft8xx init is running. In the function void FT81x_Init(void) i added Send_CMD(TOUCH_DATA_U8) and also tried Send_CMD(TOUCH_DATA_U32). The code for the data is in a seperate header file.
Could you help me out with a code example or an optimized library so i can use the touch screen?

Thank you very much.
Cheers,
Chris

Hi Chris,

I have created a program that will specifically load the capacitive touch calibration file onto the EVE display. The example includes 2 different calibration functions. One function (Calibrate_Cap_Touch) will read the calibration values from the SD card and upload them to the display. You will need an SD card in order to use this function. Please make sure to copy over the Cap_Cal.bin file to the SD card. The Cap_Cal.bin file is located in the Files for SD card folder.

The other function (MO_Calibrate) will read the calibration values from a header file and upload the data to the display. Please note, the calibration file is rather large and therefore I recommend storing the calibration values on the SD card, as opposed to your Arduino's flash memory.

Once the display is calibrated, three dots will appear on screen, along with labels listing where you are touching on the screen.

Please give this demo a shot, and let me know if you have any other questions or concerns.

Cheers,
Daniel

Hey Daniel,
thank you very much for your help. The touch screen works fine now. I included your code into the EVE School project and the touch works after you calibrate the touch on the calibration screen.
Thumbs up (y) for the superb support.

Cheers,
Chris

Hi Danile,
Now I am working with your capacitive touch screen display. I used your MO_Calibrate code. Because I don't have SD card option. I have modified few things in your MO_Calibrate code. But the touch functions are never working. Herewith I have attached my full project code also. Please let me know, is there any limitation for your display board?. Please help me.

Hi Suresh,

It looks like your photo didn't upload properly. Please try uploading the photo again.

Also, are you sure you are using a capacitive touch screen? In your other posts, it looks like you are using a resistive touch screen.

Cheers,
Daniel

Hi Daniel,
Thanks for your reply. I uploaded new photo. Please go through my attachments. Yes, Daniel. I bought two types of display. I bought resistive and capacitive also. Currently I worked with your resistive display. But I have to improve touch accuracy. I will handle that issue. If I cannot fix the issue, I will ask you. As of now I am working with capacitive touch screen display. Yesterday I got the above issue. Means that, the capacitive touch is never working. I have attached my code and snapshot also. If you need more explanation, please go with my previous reply in this same post. I explained that how i used my calibrator code.

Hi Suresh,

Thank you for clarifying.

Could you try replacing the following lines in MO_Calibrate:
with
Then give it a shot.

Cheers,
Daniel

Hi Daniel,
Awesome. It's working well. Thank you so much for your support.