AT42QT2120 Datasheet

21
9634E–AT42–06/12
AT42QT2120
5.5 Addresses 3 – 4: Key Status
KEY0 – KEY11: These bits indicate which keys are in detection, if any. Touched keys report as
1, untouched or disabled keys report as 0. A change in these bytes will cause the CHANGE
line
to trigger.
5.6 Address 5: Slider Position
SLIDER POSITION: Reports the slider/wheel position. This value is only valid when the SDET
bit in the Detection Status byte is set. A change in this value will cause the CHANGE
line to
assert low.
5.7 Address 6: Calibrate
CALIBRATE COMMAND: Writing any nonzero value into this address triggers the device to
start a calibration cycle. The CALIBRATE flag in the detection status register is set when the
calibration begins and clears when the calibration has finished.
5.8 Address 7: Reset
RESET COMMAND: Writing any nonzero value to this address triggers the device to reset.
Table 5-5. Key Status
Address Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
3 KEY7 KEY6 KEY5 KEY4 KEY3 KEY2 KEY1 KEY0
4 Reserved KEY11 KEY10 KEY9 KEY8
Table 5-6. Slider Position
AddressBit 7Bit 6Bit 5Bit 4Bit 3Bit 2Bit 1Bit 0
5 SLIDER POSITION
Table 5-7. Calibrate
Address Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
6 CALIBRATE COMMAND
Table 5-8. Reset
Address Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
7 RESET COMMAND