Getting touchy performance with your screen's touchscreen? Resistive touch screens are incredibly popular as overlays to TFT and LCD displays. If you want to connect one to a computer, you need something to handle the analog-to-digital conversion. Most converters we've found are not very easy to use, and are 'fixed' - making them difficult to calibrate. The AR1100 is a nice chip that solves this problem by acting as a touch->USB converter, and also comes with calibration software. The calibration software is Windows only, but once you've calibrated, you can use the screen on any OS. The AR1100 shows up as a regular Mouse or Digitizer HID device, so no drivers are required. We've tested it successfully on Mac, Windows, and Debian Linux (Raspbian on a Raspberry Pi). Other Linux distributions may or may not work, but if you're running Linux, you're probably used to that.

This breakout board features the AR1100, which offers both USB and UART interfaces. 99% of the time, you'll want to use the USB interface; however, there is some functionality available for extracting TTL UART data (see the datasheet for details). There is also a red LED that lights up to indicate when a touch has been detected.

For screens with 1mm pitch FPC cables, you can plug the cable directly into the connector. The majority of medium/large touchscreens have that kind of connector. If you have another kind of touch screen, the four X/Y contacts are available on 0.1" pitch breakouts so you can hand-solder or wire them. We set this breakout up for 4-wire sensing only.

You can pretty much plug and play to get started. For more details including calibration software, check out the AR1100 page. Plug any 1mm-pitch 4-wire resistive touchscreen to the on-board FPC connector. When you plug into a computer's USB-C port, you should see a new device, and touching the screen will cause the mouse cursor to move around.