pca9539d NXP Semiconductors, pca9539d Datasheet - Page 9

• Manufacturer Part Number: pca9539d
• Description: 16-bit I2c And Smbus, Low Power I/o Port With Interrupt And Reset
• Manufacturer: NXP Semiconductors

NOTE: Transfer can be stopped at any time by a STOP condition.
NOTES: Transfer of data can be stopped at any moment by a STOP condition. When this occurs, data present at the latest acknowledge phase is valid (output mode).
It is assumed that the command byte has previously been set to 00 (read input port port register).
READ FROM PORT 0
DATA INTO PORT 0
READ FROM PORT 1
DATA INTO PORT 1
SDA
SCL
INT
S
1
S
1
2
1
1
3
1
1
t
IV
4
0
1
slave address
5
1
0
6
A1 A0
1
7
A1 A0
R/W ACKNOWLEDGE
8
1
acknowledge
from slave
9
A
FROM SLAVE
R/W
0
7
A
6
t
IR
5
4
I0.x
COMMAND BYTE
3
2
Figure 9. READ input port register — scenario 1
1
0
A
ACKNOWLEDGE
FROM MASTER
Figure 8. READ from register
acknowledge
from slave
7
6
A
at this moment master-transmitter
becomes master-receiver and
slave-receiver becomes
slave-transmitter
5
S
4
I1.x
1
3
1
2
slave address
1
1
0
0
1
A
ACKNOWLEDGE
FROM MASTER
A1 A0
7
6
acknowledge
from slave
R/W
1
5
MSB
4
A
I0.x
MSB
3
data from upper
or lower byte of
2
register
last byte
1
data from lower
DATA
or upper byte
of register
0
first byte
DATA
A
ACKNOWLEDGE
FROM MASTER
7
LSB
no acknowledge
from master
6
acknowledge
from master
NA
5
LSB
4
SW02207
P
I1.x
A
3
NON ACKNOWLEDGE
2
1
FROM MASTER
0
SW02208
1
P