pca8885 NXP Semiconductors, pca8885 Datasheet - Page 8

• Manufacturer Part Number: pca8885
• Description: Capacitive 8-channel Proximity Switch With Auto-calibration And Very Low Power Consumption
• Manufacturer: NXP Semiconductors

NXP Semiconductors
9. Commands
PCA8885
Objective data sheet
9.1 Command overview
9.2 Command: soft-reset
9.3 Commands: Sleep and wake-up
The operation of the PCA8885 can be controlled by 12 commands and four configuration-
and status-registers (see
programmed using single commands without associated data transfer. The configuration
register can however also be written using the write-config command. The clock and mask
registers can only be programmed using the write-clock and write-mask commands.
Table 4.
Reset takes place during power-on of the circuit. There is no external hardware reset
input.
During operation, the device can be reset using the soft-reset command. The sensor
channels and all registers are reset to the default values and the int-over-I
terminated. It does not affect the state of the analog section except for those functions that
are controlled by configuration bits.
Sleep mode is implemented to save power during periods where no sensor activity is
expected or supported.
In sleep mode, most of the circuit parts are put in power-down mode, in particular all
analog blocks consuming static and dynamic power. This includes the oscillator, thus no
internal activity remains. Also the voltage regulator is powered down, to reduce its
standalone power consumption.
Command
soft-reset
clear-INT
sleep
wake-up
write-config 0011 0000
read-config 0011 0011
write-clock
read-clock
write-mask
read-mask
int-over-I
read-sensor -
2
C 0011 1100
Commands of PCA8885
Operation
code
0000 0000
0000 0011
0000 0101
0000 0110
0011 0101
0011 0110
0011 1001
0011 1010
All information provided in this document is subject to legal disclaimers.
Rev. 1 — 24 November 2011
Description
brings chip to reset state
deactivates interrupt generation on pin
INT
enter sleep mode
enter active mode
write configuration register
read configuration register
write clock setting register
read clock setting register
write the mask register
read the mask register
put the device in int-over-I
read sensor state register and clears
the INT line
Section 10 on page
Capacitive 8-channel proximity switch with auto-calibration
10). Several configuration settings can be
2
C mode
Transfer
type
command
command
command
command
write 1 byte
read 1 byte
write 1 byte
read 1 byte
write 1 byte
read 1 byte
command
direct read
PCA8885
© NXP B.V. 2011. All rights reserved.
Reference
Section
Section 10.2.2.2
Section 10.2.2.1
Section 9.3
Section 10.2
Section 10.4
Section 10.5
Section 10.2.2.1
Section
Section 10.2.2.1
2
C mode is
9.2,
9.4,
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