I just purchased the EA DOGXL160-7 display and a touch panel. I am looking for data sheets on the above-mentioned product. The only thing I could find on your website is the application example for the touch panel which shows how to connect the touch panel to an ATmega AVR processor and nothing else. This application example does not provide any information on how the touch panel works.
The touch panel EA TOUCH160-1 (which corresponds to the EA DOGXL160-7) is an analog, 4-wire, resistive touch display. As you see, the 4 wires are connected to the 4 edges on the touch panel.
When you press on it, there will be an electrical contact between the 2 layers of the touch panel. Your ATmega will do something like this:
(1) Connect 5V to the upper edge and 0V to the lower edge.
(2) Read the voltage on the right/left edge
(3) Connect 5V to left edge and 0V to the left edge
(4) Read the voltage on the upper/lower edge
(2) Read 2.5V and (4) reads 1V
This 2.5V reading tells you that the “key press” was on a horizontal line which is in the middle of the panel. And the second reading 1.0V indicates the “key press” on a vertical line near the right edge. The “key” was pressed on the coordinates where both lines intersect.
There’s an interesting application note #341 on Atmel’s website:
The code that goes with it is here, if you search #341: