pca9557bs NXP Semiconductors, pca9557bs Datasheet - Page 11

• Manufacturer Part Number: pca9557bs
• Description: 8-bit I2c And Smbus I/0 Port With Reset
• Manufacturer: NXP Semiconductors

NXP Semiconductors
PCA9557_5
Product data sheet
Fig 14. Write to output port register
Fig 15. Write to I/O configuration or polarity inversion registers
SDA
write to port
data out from port
SDA
SCL
SCL
S
START condition
S
START condition
1
1
0
0
8.4 Bus transactions
2
2
0
0
slave address
slave address
3
3
1
1
Data is transmitted to the PCA9557 registers using Write Byte transfers (see
and
transfers (see
Fig 13. Acknowledgement on the I
4
4
1 A2 A1 A0
1 A2 A1 A0
Figure
5
5
6
6
7
7
SCL from master
15). Data is read from the PCA9557 registers using Read and Receive Byte
R/W
R/W
8
8
0
by transmitter
0
Figure 16
data output
by receiver
data output
9
9
A
acknowledge
from slave
A
acknowledge
from slave
0
0
Rev. 05 — 12 September 2007
0
0
and
condition
command byte
command byte
START
0
0
S
0
0
Figure
0
0
0
0
2
C-bus
17).
0
1 1/0
1
1
A
acknowledge
from slave
A
acknowledge
from slave
8-bit I
2
2
C-bus and SMBus I/O port with reset
data to register
data to port
DATA 1
DATA
acknowledgement
not acknowledge
clock pulse for
acknowledge
8
t
v(Q)
A
acknowledge
from slave
A
acknowledge
from slave
PCA9557
© NXP B.V. 2007. All rights reserved.
002aaa987
DATA 1 VALID
STOP
condition
P
9
STOP
condition
P
002aad281
002aad282
Figure 14
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