Philips Semiconductors
4-bit I2C and SMBus I/O port
Objective data sheet
PCA9536
slave address
acknowledge
from slave
S1 0 0 0 0 0 1 0 A
R/W
acknowledge
from slave
slave address
acknowledge
from slave
acknowledge
data from register from master
COMMAND BYTE
A S 1 0 0 0 0 0 11 A
R/W
at this moment master-transmitter
becomes master-receiver and
slave-receiver becomes
slave-transmitter
DATA
A
first byte
data from register
no acknowledge
from master
Figure 7. READ from register
DATA
last byte
NA P
SW02196
SCL
SDA
READ FROM
PORT
1 2345 6 78 9
slave address
data from port
S1 00 00 01 1 A
start condition
R/W acknowledge
from slave
DATA 1
data from port
A
acknowledge
from master
DATA 4
NA P
no acknowledge
from master
stop
condition
DATA INTO
PORT
DATA 2
DATA 3
tph
tps
NOTES:
1. This figure assumes the command byte has previously been programmed with 00h.
2. Transfer of data can be stopped at any moment by a stop condition.
Figure 8. READ input port register
DATA 4
SW02197
2004 Aug 20
7