Datasheet

9502A–AT42–07/08

AT42QT2160

7.17 Address 20: Slider Control

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)

7.18 Address 21: Slider Options

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.

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)

Table 7-17. Slider Control

Addressb7b6b5b4b3b2b1b0

20 HYST NUM_KEYS

Table 7-18. Slider Options

Addressb7b6b5b4b3b2b1b0

21 00000 RESOLUTION

Table 7-19. Resolution

Value Resolution Value Resolution

0 8 bits (0-255) 4 4 bits (0-15)

1 7 bits (0-127) 5 3 bits (0-7)

2 6 bits (0-63) 6 2 bits (0-3)

3 5 bits (0-31)