I wanted to attach an LCD touch screen to the top of the kit. The lid has a diagonal of about nine inches (22cm) so a 6, 7 or 8 inch screen will do.
The options are:
Decision: I chose an 8.4” LVDS display from ICOP, LCD-AU084-SET (Qualification later). I actually wanted a 6.4” display but it wasn’t available until later.
A 4 wire resistive (single touch) touch panel will do. A USB interface is desirable.
A key issue is whether there is a Windows CE driver for the touch screen. The off-the-shelf screen (as in 1.) don’t tend indicate CE compatibility for touch. Enquiries suggested to try the CE driver at:
but no guarantees were given.
The ICOP LVDS displays come with a touch screen option that has a USB interface.
I ordered the LCD-AU084-SET form ICOP in Taiwan and it arrived about 5 days later. This cost about $US200 plus shipping. I also ordered a Mini PCU WiFi card for about $US30 as part of the same order. (This fits into the internal Mini PCI slot).
On examination I realised it didn’t have the touch panel. I should have ordered LCD-AU084-U-SET; the extra U was missing. The touch panel was shipped later and cost about $US40 plus shipping. !@#$%^*&$#@!
In the next few Blogs I will cover setting up the display and touch screen with the kit. I use the LVDS display as above.
This sequence does not cover using the TFT Flat Panel.
Here is a diagram of how a resistive touch panel works (Ref https://www.sparkfun.com/commerce/tutorial_info.php?tutorials_id=139 .. Thanks A1ronzo )
The four pins control 4 buss bars located around the peripheral of the touchscreen. In order to read either an x or a y position, two opposing bars need to be powered and a third orthogonal bar is used to measure the divided voltage.
This configuration means that the voltage, ground, and sense bar need to be continually switched in order to quickly read x and y positions. Here is how I hooked up the touchscreen