pca8575 NXP Semiconductors, pca8575 Datasheet - Page 8

• Manufacturer Part Number: pca8575
• Description: Remote 16-bit I/o Expander For I2c-bus With Interrupt
• Manufacturer: NXP Semiconductors

NXP Semiconductors
PCA8575_2
Product data sheet
Fig 11. Write mode (output)
SDA
SCL
data output from port
P05 output voltage
P05 pull-up output current
P16 output voltage
P16 pull-up output current
INT
write to port
S A6
START condition
1
A5 A4 A3 A2 A1 A0 0
2
8.3 Reading from a port (Input mode)
slave address
3
4
All ports programmed as input should be set to logic 1. To read, the master
(microcontroller) first addresses the slave device after it receives the interrupt. By setting
the last bit of the byte containing the slave address to logic 1 the Read mode is entered.
The data bytes that follow on the SDA are the values on the ports.
If the data on the input port changes faster than the master can read, this data may be
lost.
5
6
7
R/W
8
9
A
acknowledge
from slave
07
P
06 1
P
Rev. 02 — 21 March 2007
data to port 0
P05
04
P
03
P
02
P
Remote 16-bit I/O expander for I
01
P
I
t
trt(pu)
d(rst)
00
P
A
acknowledge
from slave
17
P
t
v(Q)
I
1
P16
OH
data A0 and B0 valid
15
P
data to port 1
14
P
13
P
12
P
11
I
P
trt(pu)
10
P
A
acknowledge
from slave
2
C-bus with interrupt
data A0 and B0 valid
PCA8575
t
© NXP B.V. 2007. All rights reserved.
v(Q)
I
OH
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