Search by Tags

Resistive Touch Screen (Linux)

 

Article updated at 06 Feb 2019
Compare with Revision




Subscribe for this article updates

General information

Resistive touch works out-of-the-box in all Toradex modules. However, depending on your touchscreen, some calibration may be needed.

Colibri X1 connector Colibri function
14 TSPX
16 TSMX
18 TSPY
20 TSMY
Apalis X1 connector Apalis function
315 AN1_TSPX
317 AN1_TSMX
319 AN1_TSPY
321 AN1_TSMY

Apalis T30, Apalis iMX6, Colibri T30, Colibri iMX6

The Apalis T30, Apalis iMX6, Colibri T30 and Colibri iMX6 offer a 4-wire resistive touch interface via ST Microelectronics STMPE811, which is connected to the SoC through I2C. The STMPE811 does not support 5-wire operation mode.

Please consult the Microelectronics STMPE811 documentation for more information.

Apalis TK1

The Apalis TK1 offers a 4-wire resistive touch interface implemented via the K20 companion MCU.

Colibri iMX7, Colibri iMX6ULL, Colibri iMX8X

The Colibri iMX7, Colibri iMX6ULL and Colibri iMX8X offer a 4-wire resistive touch interface using the Analog Device AD7879-1 Touchscreen Controller, which is connected to the SoC through I2C. The AD7879-1 does not support 5-wire operation mode.

Please consult the Analog Device AD7879-1 documentation for more information.

Colibri VF61, Colibri T20

The Colibri VF61 and Colibri T20 offer a 4-wire resistive touch interface via the Wolfson WM9715L audio codec.

Please consult the Wolfson WM9715 documentation for more information.

Colibri VF50

The touch interface is provided by using the internal ADC input of the Vybrid SoC.

Note: Make sure to check the modules datasheet for additional information.

Touch Calibration

BSP 2.x automatically performs a calibration upon first boot and will continue to ask for calibration in every boot until it is successfully completed.

The calibration application can be found in /usr/bin/xinput_calibrator.

Touch Calibration (BSP 1.x)