CRTOUCH Datasheet, PDF (15/68 Pages) Freescale Semiconductor, Inc – Capacitive and Resistive Touch Sensing Application Specific IC.

Functional Description
2.1.6 Resistive gestures
The CRTouch controller has built-in gestures detection capabilities with unique support for zoom and rotate multi-touch
gestures, as well as single touch slides. This feature offloads the host processor of continuous coordinate reading and processing
for gesture detection.
2.1.6.1 Slide
A slide is detected for linear motion in any region of the screen in a direction parallel to any axis of the screen. This means that
any motion that varies only one axis can be detected as a slide. The detection algorithm supports a deviation of 7.5° from the
axis direction to still consider the motion as a slide. The following figure shows the valid ranges for a slide motion.
Figure 12. Slide valid regions
The slide gesture is enabled through the slide enable bit in the Configuration Register, and it is reported through the Slide Event
bit in the Status Register 1. A slide can be performed in four different directions: horizontal or vertical, positive or negative in
each case. The direction of the gesture is reported in the Status Register 2 through the Slide Direction [1:0] bits. The following
table shows the reported value for each case.
Motion
X0 < X1, Y0 = Y1
X0 > X1, Y0 = Y1
Y0 < Y1, X0 = X1
Y0 > Y1, X0 = X1
Table 4. Slide gesture directions
Direction
Slide Direction [1:0]
Horizontal positive
00
Horizontal negative
01
Vertical positive
10
Vertical negative
11
The slide gesture is reported when the motion distance is higher than a configurable threshold. This threshold is a portion of the
screen resolution across each axis. For a vertical slide, a portion of the Y resolution is the threshold and for a horizontal slide,
a portion of the X resolution is the threshold. This portion is defined by the Slide Steps register value. For a value of ten, the
CRTouch Data Sheet, Rev. 3
Freescale Semiconductor
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