SBC Axel SBC/Interfaces and Connectors/Touchscreen
| History | |||
|---|---|---|---|
| Version | Issue Date | Notes | |
| 1.0.0 | Oct 2020 | First DESK release | |
Touchscreen[edit | edit source]
Description[edit | edit source]
The 4-wire resistive touch controller signals are routed to J50, which is a 4 pin (1mm pitch vertical) ZIF connector for the 4-wires resistive controller.
The touch controller is a TI TSC2003 device, connected to the I²C2 bus (address 0x1001000b).
Signals[edit | edit source]
The following table describes the interface signals:
| Pin# | SOM Pin# | Pin name | Pin function | Pin Notes |
|---|---|---|---|---|
| 1 | - | TSC_YP | Touch controller Y+ | |
| 2 | - | TSC_XP | Touch controller X+ | |
| 3 | - | TSC_YM | Touch controller Y- | |
| 4 | - | TSC_XM | Touch controller X- |
Device mapping[edit | edit source]
The device is typically mapped to /dev/touchscreen0 device in Linux.
The touch controller is attached to the generic Linux input event interface (evdev).
Device usage[edit | edit source]
The simplest tools for touch screen management are the tslib library and ts_tools utilities. To calibrate the touch screen, the ts_calibrate command line tool is available.
After calibration, the touch screen can be tested using the graphical ts_test utility or the ts_print command line tool.
