pca9554ad NXP Semiconductors, pca9554ad Datasheet - Page 11

• Manufacturer Part Number: pca9554ad
• Description: 8-bit I2c And Smbus I/o Port With Interrupt
• Manufacturer: NXP Semiconductors

NXP Semiconductors
PCA9554_9554A_7
Product data sheet
Fig 14. Read from register
Fig 15. Read Input Port register
SDA
(cont.)
data into
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.
read from
port
INT
S
START condition
SDA
SCL
port
S
(repeated)
START condition
0
0
S
1
START condition
slave address
1
1
t
0
0
v(INT_N)
slave address
0
2
0 A2 A1 A0 0
1
slave address
0 A2 A1 A0 1
3
0
acknowledge
4
0 A2 A1 A0 1
from slave
acknowledge
5
R/W
from slave
6
acknowledge
R/W
from slave
7
A
R/W
t
h(D)
A
8
9
A
Rev. 07 — 13 November 2006
at this moment master-transmitter becomes master-receiver
and slave-receiver becomes slave-transmitter
command byte
DATA 2
data from register
DATA (first byte)
t
rst(INT_N)
data from port
DATA 1
acknowledge
DATA 3
from slave
acknowledge
from master
acknowledge
from master
8-bit I
A
A
t
su(D)
(cont.)
2
PCA9554/PCA9554A
C-bus and SMBus I/O port with interrupt
A
DATA 4
data from register
DATA (last byte)
data from port
DATA 4
no acknowledge
no acknowledge
from master
from master
© NXP B.V. 2006. All rights reserved.
NA
NA
002aac475
002aac474
P
STOP
condition
P
STOP
condition
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