Datasheet

PCA9539_PCA9539R All information provided in this document is subject to legal disclaimers. © NXP Semiconductors N.V. 2014. All rights reserved.
Product data sheet Rev. 8 — 26 November 2014 7 of 38
NXP Semiconductors
PCA9539; PCA9539R
16-bit I
2
C-bus and SMBus low power I/O port with interrupt and reset
6. Functional description
Refer to Figure 4 “Block diagram of PCA9539; PCA9539R”.
6.1 Device address
6.2 Registers
6.2.1 Command byte
The command byte is the first byte to follow the address byte during a write transmission.
It is used as a pointer to determine which of the following registers will be written or read.
Fig 8. PCA9539; PCA9539R device address
R/W
002aad724
1 1 1 0 1 A1 A0
programmable
slave address
fixed
Table 4. Command byte
Command Register
0 Input port 0
1 Input port 1
2 Output port 0
3 Output port 1
4 Polarity inversion port 0
5 Polarity inversion port 1
6 Configuration port 0
7 Configuration port 1