pca9574 NXP Semiconductors, pca9574 Datasheet - Page 14

• Manufacturer Part Number: pca9574
• Description: 8-bit I2c-bus And Smbus, Level Translating, Low Voltage Gpio With Reset And Interrupt
• Manufacturer: NXP Semiconductors

NXP Semiconductors
9. Bus transactions
PCA9574_1
Product data sheet
Fig 11. Write to Output port register
Fig 12. Write to Polarity inversion, Bus-hold enable, Pull-up/pull-down selector, Configuration, Interrupt mask
SDA
SDA
write to port
data out from port
data to register
and Interrupt status registers
SCL
SCL
S
START condition
S
START condition
1
1
0
0
2
2
1
1
slave address
slave address
3
3
0
0
Data is transmitted to the PCA9574 registers using ‘Write Byte’ transfers (see
and
Data is read from the PCA9574 registers using ‘Read Byte’ transfers (see
Figure
4
4
0
0
Figure
5
5
0
0
14).
6
6
0 A0
0 A0
7
7
12).
R/W
R/W
8
8
0
0
9
9
A
A
acknowledge
from slave
acknowledge
from slave
0
0
0
0
Rev. 01 — 15 May 2008
8-bit I
command byte
command byte
0
0
0
0
2
0
0
C-bus and SMBus, level translating, low voltage GPIO
0
0
0
1 1/0
1
A
acknowledge
from slave
A
acknowledge
from slave
data to register
data to port
DATA 1
DATA
t
v(Q)
A
acknowledge
from slave
A
acknowledge
from slave
PCA9574
© NXP B.V. 2008. All rights reserved.
DATA 1 VALID
STOP
condition
P
STOP
condition
P
002aad057
Figure 13
002aad058
Figure 11
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and