CAP1188-1-CP-TR Datasheet, PDF (47/93 Pages) Microchip Technology – 8 Channel Capacitive Touch Sensor with 8 LED Drivers

5.6
Configuration Registers
8 Channel Capacitive Touch Sensor with 8 LED Drivers
Datasheet
Table 5.10 Configuration Registers
ADDR R/W REGISTER
B7
B6
B5
B4
B3
B2
B1
B0
DEFAULT
20h
R/W Configuration
TIMEOUT
WAKE_ DIS_ DIG_ DIS_ ANA_ MAX_
CFG
NOISE
NOISE
DUR_EN
-
-
-
A0h
(rev B)
20h
(rev C)
44h
R/W
Configuration 2
INV_LINK_
TRAN
ALT_
POL
BLK_PWR_ BLK_POL_
CTRL
MIR
SHOW_
RF_
NOISE
DIS_
RF_
NOISE
-
INT_
REL_n
40h
5.6.1
The Configuration registers control general global functionality that affects the entire device.
Configuration - 20h
Bit 7 - TIMEOUT - Enables the timeout and idle functionality of the SMBus protocol.
„ ‘0’ (default for Functional Revision C) - The SMBus timeout and idle functionality are disabled. The
SMBus interface will not time out if the clock line is held low. Likewise, it will not reset if both the
data and clock lines are held high for longer than 200us. This is used for I²C compliance.
„ ‘1’ (default for Functional Revision B) - The SMBus timeout and idle functionality are enabled. The
SMBus interface will time out if the clock line is held low for longer than 30ms. Likewise, it will reset
if both the data and clock lines are held high for longer than 200us.
Bit 6 - WAKE_CFG - Configures the operation of the WAKE pin.
„ ‘0’ (default) - The WAKE pin is not asserted when a touch is detected while the device is in Standby.
It will still be used to wake the device from Deep Sleep when driven high.
„ ‘1’ - The WAKE pin will be asserted high when a touch is detected while the device is in Standby.
It will also be used to wake the device from Deep Sleep when driven high.
Bit 5 - DIS_DIG_NOISE - Determines whether the digital noise threshold (see Section 5.19, "Sensor
Input Noise Threshold Register") is used by the device. Setting this bit disables the feature.
„ ‘0’ - The digital noise threshold is used. If a delta count value exceeds the noise threshold but does
not exceed the touch threshold, the sample is discarded and not used for the automatic re-
calibration routine.
„ ‘1’ (default) - The noise threshold is disabled. Any delta count that is less than the touch threshold
is used for the automatic re-calibration routine.
Bit 4 - DIS_ANA_NOISE - Determines whether the analog noise filter is enabled. Setting this bit
disables the feature.
„ ‘0’ (default) - If low frequency noise is detected by the analog block, the delta count on the
corresponding channel is set to 0. Note that this does not require that Noise Status bits be set.
„ ‘1’ - A touch is not blocked even if low frequency noise is detected.
Bit 3 - MAX_DUR_EN - Determines whether the maximum duration recalibration is enabled.
„ ‘0’ (default) - The maximum duration recalibration functionality is disabled. A touch may be held
indefinitely and no re-calibration will be performed on any sensor input.
„ ‘1’ - The maximum duration recalibration functionality is enabled. If a touch is held for longer than
the MAX_DUR bit settings, then the re-calibration routine will be restarted (see Section 5.8).
SMSC CAP1188
47
DATASHEET
Revision 1.32 (01-05-12)