Datasheet

1 2 3 4 5 6 7 8 9
S 0 1 0 0 A
2 A1 A0 1
A A
I0.x
A
I1.x
A
I0.x
1
I1.x
P
R
/W
SCL
S
DA
INT
t
p
h
00 10 03
12
t
p
s
t
p
h
t
p
s
11 12
Read From Port 0
Data Into Port 0
Read From Port 1
Data Into Port 1
Data 02Data 01Data 00 Data 03
DataDataData 10
Acknowledge
From Slave
Acknowledge
From Master
Acknowledge
From Master
Acknowledge
From Master
No Acknowledge
From Master
t
iv
t
ir
PCA9555
SCPS131E–AUGUST2005–REVISEDMAY2008......................................................................................................................................................... www.ti.com
A.TransferofdatacanbestoppedatanytimebyaStopcondition.Whenthisoccurs,datapresentatthelatest
acknowledgephaseisvalid(outputmode).Itisassumedthatthecommandbytepreviouslyhasbeensetto00(read
InputPortregister).
B.Thisfigureeliminatesthecommandbytetransfer,arestart,andslaveaddresscallbetweentheinitialslaveaddress
callandactualdatatransferfromthePport(seeFigure8forthesedetails).
Figure10.ReadInputPortRegister,Scenario2
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