PCA9552_5

© Koninklijke Philips Electronics N.V. 2006. All rights reserved.

Product data sheet

Rev. 05 — 9 March 2006

6 of 28

Philips Semiconductors

PCA9552

6.2.1 Control Register definition

6.3 Register descriptions

6.3.1 INPUT0 - Input register 0

The Input register 0 reflects the state of the device pins (inputs LED0 to LED7). Writes to

this register will be acknowledged but will have no effect.

Remark: The default value ‘X’ is determined by the externally applied logic level (normally

6.3.2 INPUT1 - Input register 1

The Input register 1 reflects the state of the device pins (inputs LED8 to LED15). Writes to

this register will be acknowledged but will have no effect.

Remark: The default value ‘X’ is determined by the externally applied logic level (normally

Table 3:

Register summary

B3

B2

B1

B0

Symbol

Access

Description

0000

INPUT0

read only

input register 0

0001

INPUT1

read only

input register 1

0010

PSC0

read/write

frequency prescaler 0

0011

PWM0

read/write

PWM register 0

0100

PSC1

read/write

frequency prescaler 1

0101

PWM1

read/write

PWM register 1

0110LS0

read/write

LED0 to LED3 selector

0111LS1

read/write

LED4 to LED7 selector

1000LS2

read/write

LED8 to LED11 selector

1001LS3

read/write

LED12 to LED15 selector

Table 4:

INPUT0 - input register 0 description

Bit

7

6

5

4

3

2

1

0

Symbol

LED7

LED6

LED5

LED4

LED3

LED2

LED1

LED0

Default

XXXXXXXX

Table 5:

INPUT1 - input register 1 description

Bit

7

6

5

4

3

2

1

0

Symbol

LED15

LED14

LED13

LED12

LED11

LED10

LED9

LED8

Default

XXXXXXXX