at42qt2160 ATMEL Corporation, at42qt2160 Datasheet - Page 31

• Manufacturer Part Number: at42qt2160
• Description: Qslide?, 16-key Qmatrix? Sensor Ic
• Manufacturer: ATMEL Corporation

7.17
7.18
9502A–AT42–07/08
Address 20: Slider Control
Address 21: Slider Options
Table 7-17.
Table 7-18.
HSYT: Set the hysteresis value for the slider’s reported position. Hysteresis is the number of
positions the user has to move back, before the new touch position is reported when the
direction of scrolling is changed and during first scroll after touch down.
At lower resolutions, where skipping of reported positions will be noticed, hysteresis can be set
to 0 (1 position). At higher resolutions (6...8 bits), it would be recommended to have a hysteresis
of at least 2 positions or more.
HYST can range from 0 (1 position) to 15 (16 positions). The hysteresis is carried out at 8 bits
resolution internally and scaled to the desired resolution; therefore at resolutions lower than 8
bits, there might be a difference of 1 reported position from the HYST setting, depending on
where the touch down is.
Note: it is not valid to have a hysteresis value more than the available positions in a resolution.
For example, do not have a HYST of 5 positions with a resolution of 2 bits (4 positions).
NUM_KEYS: Set the number of keys to be used in the slider. For proper slider operation, valid
values are between 2 and 8. Setting a value of 0, will disable the slider.
HYST Default: 0 (1 position), NUM_KEYS Default: 5 (5 keys)
RESOLUTION: Resolution of reported position of touch on the slider. Valid values are between
0 (8 bits) to 6 (2 bits). The keys used for the slider starts at X0 and is on the Y0 line.
Table 7-19.
Note: For better stability of the reported position at higher resolutions, increase the number of
keys used to construct the slider, reduce the front panel thickness, reduce the loading on the
slider keys or increase the burst length to gain more signal.
Default: 4 (4 bits)
Address
Address
20
21
Value
0
1
2
3
Slider Control
Slider Options
Resolution
b7
b7
0
b6
b6
0
8 bits (0-255)
7 bits (0-127)
6 bits (0-63)
5 bits (0-31)
Resolution
HYST
b5
b5
0
b4
b4
0
Value
b3
b3
4
5
6
0
b2
b2
NUM_KEYS
AT42QT2160
RESOLUTION
4 bits (0-15)
Resolution
3 bits (0-7)
2 bits (0-3)
b1
b1
b0
b0
31