GOODIX CONFIDENTIAL
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8. Reading Coordinate in Gesture Mode
In Gesture mode, when 0x814B is not 0, the host can describe the wakeup trajectory of user by reading the gesture
features and gesture coordinates.
Gesture features: the host reads registers ranged from 0x814D to 0x816C and captures the following Gesture
features: start coordinate, end coordinate, trajectory width, trajectory height, trajectory central point and the four
extreme points of the trajectory. The host can sketchily describe the wakeup trajectory of user by these features and
the gesture type indicated by 0x814B.
Gesture coordinates: the host obtains the number of touch points of the trajectory by reading the register 0x814C.
And then it reads the registers ranged from 0x9420 to 0x951F based on the principle that every four register
correspond to one touch point. Finally, the host can describe the real touch trajectory of user by synthesizing these
information.
9. Time Limit for Downloading HotKnot Firmware
In HotKnot mode, to ensure the I2C transmission rate and considering factors such as time expended by system
calls and user experience, the time limit for transmitting HotKnot firmware should be within 800ms, that is to say,
the I2C transmission rate should be no less than 200Kbps. FAEs should make sure this requirement is fulfilled
when debugging for customers.
Since HotKnot may employ the frequencies such as 200K, 250K, 300K, 350K, 400K, 450K and etc, in order to
avoid interference caused by trace routing, it is recommended that the I2C transmission rate should be different
from the above frequencies, with a deviation greater than 10KHz, for example, 325Khz.
10. Revision History
Revision
Date
Description
Rev.00
2014-08-04
Preliminary version
