AT42QT2160_14 Datasheet, PDF (25/51 Pages) ATMEL Corporation – 16-key QMatrix Touch Sensor IC

These bits indicate the general status of the device. A change in this byte will cause the CHANGE line to trigger.
RESET: this bit is set after a reset. This bit is clear after this byte is read back by the host.
CYCLE OVERRUN: this bit is set if the cycle time is more than 16 ms. It will be cleared when the cycle time is less
than 16ms.
Note: holding any of the I²C lines, for clock stretching or other purposes, will increase the cycle time.
CC: this common change bit is set if all the selected keys (address 78 – 79) have a signal change of more than half
the detection threshold, NTHR. The CC bit is not debounced.
This bit can be used to indicate a common change in signals, for example, in a notebook application, where the
cover is closing, so that the host can suppress key detections.
Note: the CC bit will be set to 1 if no keys are selected to be in the Common Change group (see Section 6.27 on
page 34).
SDET: this bit is set if a touch is detected on the slider.
6.5 Address 3 – 4: Key Status
Table 6-5. Key Status and Numbering
Address
b7
b6
b5
b4
b3
b2
b1
b0
3
k7
k6
k5
k4
k3
k2
k1
k0
4
k15
k14
k13
k12
k11
k10
k9
k8
Address 3: detect status for keys 0 – 7
Address 4: detect status for keys 8 – 15
Each location indicates all keys in detection, if any, as a bit field; touched keys report as 1, untouched or disabled
keys report as 0. A change in this byte will cause the CHANGE line to trigger.
6.6 Address 5: Slider Touch Position
Table 6-6. Slider Touch Position
Address
b7
b6
b5
b4
b3
b2
b1
b0
5
Position
Position: Last position of the touch on the slider
A change in this byte will cause the CHANGE line to trigger.
6.7 Address 6: GPIO Read
Table 6-7. GPIO Read
Address
b7
b6
b5
b4
b3
b2
b1
b0
6
0
0
0
GPIO3 GPIO2 GPIO1
0
0
AT42QT2160 [DATASHEET]
25
9502C–AT42–09/2014