CAP1208 datasheet(32/67 Pages) MICROCHIP

32 / 67 page

8-Channel Capacitive Touch Sensor

Datasheet

DS00001570B-page 32

 2014 Microchip Technology Inc.

MTP_ALERT bit is also set. This bit is cleared when the INT bit is cleared if the condition that caused

it to be set has been removed.

Bit 0 - TOUCH - Indicates that a touch was detected. This bit is set if any bit in the Sensor Input Status

5.2.2

Sensor Input Status - 03h

The Sensor Input Status Register stores status bits that indicate a touch has been detected. A value

of ‘0’ in any bit indicates that no touch has been detected. A value of ‘1’ in any bit indicates that a

touch has been detected.

All bits are cleared when the INT bit is cleared and if a touch on the respective capacitive touch sensor

input is no longer present. If a touch is still detected, the bits will not be cleared (but this will not cause

the interrupt to be asserted).

Bit 7 - CS8 - Indicates that a touch was detected on Sensor Input 8.

Bit 6 - CS7 - Indicates that a touch was detected on Sensor Input 7.

Bit 5 - CS6 - Indicates that a touch was detected on Sensor Input 6.

Bit 4 - CS5 - Indicates that a touch was detected on Sensor Input 5.

Bit 3 - CS4 - Indicates that a touch was detected on Sensor Input 4.

Bit 2 - CS3 - Indicates that a touch was detected on Sensor Input 3.

Bit 1 - CS2 - Indicates that a touch was detected on Sensor Input 2.

Bit 0 - CS1 - Indicates that a touch was detected on Sensor Input 1.

5.3

Noise Flag Status Registers

The Noise Flag Status registers store status bits that can be used to indicate that the analog block

detected noise above the operating region of the analog detector or the RF noise detector (see Section

4.7.3, "Noise Status and Configuration"). These bits indicate that the most recently received data from

the sensor input is invalid and should not be used for touch detection. So long as the bit is set for a

particular channel, the delta count value is reset to 00h and thus no touch is detected.

These bits are not sticky and will be cleared automatically if the analog block does not report a noise

error.

APPLICATION NOTE: If the MTP detection circuitry is enabled, these bits count as sensor inputs above the MTP

threshold (see Section 4.6, "Multiple Touch Pattern Detection") even if the corresponding

delta count is not. If the corresponding delta count also exceeds the MTP threshold, it is not

counted twice.

APPLICATION NOTE: Regardless of the state of the Noise Status bits, if low frequency noise is detected on a

sensor input, that sample will be discarded unless the DIS_ANA_NOISE bit is set. As well,

if RF noise is detected on a sensor input, that sample will be discarded unless the

DIS_RF_NOISE bit is set.

Table 5.4 Noise Flag Status Registers

ADDR

R/W

DEFAULT

0Ah

Noise Flag

Status

CS8_

NOISE

CS7_

NOISE

CS6_

NOISE

CS5_

NOISE

CS4_

NOISE

CS3_

NOISE

CS2_

NOISE

CS1_

NOISE

00h

CAP1208 Datasheet(PDF) 32 Page - Microchip Technology

CAP1208 Datasheet(HTML) 32 Page - Microchip Technology

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67

Datasheet Download

Link URL