8. EDT ft5x06 based Polytouch devices¶
The edt-ft5x06 driver is useful for the EDT “Polytouch” family of capacitivetouch screens. Note that it isnot suitable for other devices based on thefocaltec ft5x06 devices, since they contain vendor-specific firmware. Inparticular this driver is not suitable for the Nook tablet.
- It has been tested with the following devices:
- EP0350M06
- EP0430M06
- EP0570M06
- EP0700M06
The driver allows configuration of the touch screen via a set of sysfs files:
- /sys/class/input/eventX/device/device/threshold:
- allows setting the “click”-threshold in the range from 0 to 80.
- /sys/class/input/eventX/device/device/gain:
- allows setting the sensitivity in the range from 0 to 31. Note thatlower values indicate higher sensitivity.
- /sys/class/input/eventX/device/device/offset:
- allows setting the edge compensation in the range from 0 to 31.
- /sys/class/input/eventX/device/device/report_rate:
- allows setting the report rate in the range from 3 to 14.
For debugging purposes the driver provides a few files in the debugfilesystem (if available in the kernel). In /sys/kernel/debug/edt_ft5x06you’ll find the following files:
- num_x, num_y:
- (readonly) contains the number of sensor fields in X- andY-direction.
- mode:
- allows switching the sensor between “factory mode” and “operationmode” by writing “1” or “0” to it. In factory mode (1) it ispossible to get the raw data from the sensor. Note that in factorymode regular events don’t get delivered and the options describedabove are unavailable.
- raw_data:
- contains num_x * num_y big endian 16 bit values describing the rawvalues for each sensor field. Note that each read() call on thisfiles triggers a new readout. It is recommended to provide a bufferbig enough to contain num_x * num_y * 2 bytes.
Note that reading raw_data gives a I/O error when the device is not in factorymode. The same happens when reading/writing to the parameter files when thedevice is not in regular operation mode.