Capacitive Touch Display 7" Ghosting operations

Technical Support
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#1

Dear all,

I have an issue with 7" Capacitive Touch Display parallel which is integrated in a machine.
Everything is working fine until somebody will clean the screen.
In some cases the touch controller will start “ghosting operations” wich never ends.
In this case a reboot of the machine is necessary.

I try to reproduce the situation in the office.
We use the the Colibri Imx6 with Iris Carrier and the touch display.
To exclude our software I use a unaffected Toradex Embedded Linux Reference Multimedia Image.
On the colibri ist start “evtest” to see the events from the touch.
When i wipe over the screen with a cloth it could happen that the “ghosting” starts.
“Evtest” shows me that the touch sends constant events with high frequency.
This situation will never stop until restart.

I also try with earthing the display, but it makes no difference.

Thank you in advance for any ideas what can help.

#2

Hi @zuellig.ct ,

Thank you for using the Toradex community.

The displays available in the Toradex Store are not intended as a volume product and should not be integrated into your final product. This is why Toradex marked these products as “Evaluation Products”. Their intent is to evaluate your setup. It can give you a rough idea of how it would work if you are planning to integrate a screen with the selected interface. You can find more information about the product states of Toradex here:

Furthermore, the Displays are not of good enough quality nor price to be used in volume. To find fitting volume products that are less costly and of better quality, we recommend Riverdi.

Best Regards
Kevin