pca9574 NXP Semiconductors, pca9574 Datasheet - Page 15

• 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
PCA9574_1
Product data sheet
Fig 13. Read from register
Fig 14. Read Input port register
read from
data into
SDA
(cont.)
port
port
INT
This figure assumes the command byte has previously been programmed with 00h.
Transfer of data can be stopped at any moment by a STOP condition.
S
START condition
S
(repeated)
START condition
SDA
0
SCL
0
1
S
START condition
slave address
1
t
v(INT_N)
0
slave address
1
0
0
0
2
1
0
slave address
0
3
0
0
acknowledge
0 A0 0
4
0
from slave
0 A0 1
acknowledge
5
R/W
0
from slave
R/W
6
0 A0 1
A
7
t
h(D)
A
R/W
8
9
A
acknowledge
from slave
at this moment master-transmitter becomes master-receiver
and slave-receiver becomes slave-transmitter
command byte
Rev. 01 — 15 May 2008
data from register
DATA (first byte)
8-bit I
t
rst(INT_N)
DATA 2
data from port
2
acknowledge
C-bus and SMBus, level translating, low voltage GPIO
DATA 1
DATA 3
from slave
acknowledge
from master
t
su(D)
A
A
(cont.)
A
acknowledge
from master
data from register
DATA (last byte)
data from port
DATA 4
DATA 4
no acknowledge
from master
PCA9574
© NXP B.V. 2008. All rights reserved.
NA
1
no acknowledge
from master
002aad059
002aad060
P
STOP
condition
P
STOP
condition
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