5
Integrated
Circuit
Systems, Inc.
ICS950908
Preliminary Product Preview
0653A—07/26/04
General I
2C serial interface information
How to Write:
Controller (host) sends a start bit.
Controller (host) sends the write address D2
(H)
ICS clock will
acknowledge
Controller (host) sends the begining byte location = N
ICS clock will
acknowledge
Controller (host) sends the data byte count = X
ICS clock will
acknowledge
Controller (host) starts sending
Byte N through
Byte N + X -1
(see Note 2)
ICS clock will
acknowledge each byte one at a time
Controller (host) sends a Stop bit
How to Read:
Controller (host) will send start bit.
Controller (host) sends the write address D2
(H)
ICS clock will
acknowledge
Controller (host) sends the begining byte
location = N
ICS clock will
acknowledge
Controller (host) will send a separate start bit.
Controller (host) sends the read address D3
(H)
ICS clock will
acknowledge
ICS clock will send the data byte count = X
ICS clock sends
Byte N + X -1
ICS clock sends
Byte 0 through byte X (if X
(H)
was written to byte 8).
Controller (host) will need to acknowledge each byte
Controllor (host) will send a not acknowledge bit
Controller (host) will send a stop bit
*See notes on the following page.
ICS (Slave/Receiver)
T
WR
ACK
P
stoP bit
X
Byt
e
Index Block Write Operation
Slave Address D2(H)
Beginning Byte = N
WRite
starT bit
Controller (Host)
Byte N + X - 1
Data Byte Count = X
Beginning Byte N
T
starT bit
WR
WRite
RT
Repeat starT
RD
ReaD
Beginning Byte N
Byte N + X - 1
N
Not acknowledge
PstoP bit
Slave Address D3(H)
Index Block Read Operation
Slave Address D2(H)
Beginning Byte = N
ACK
Data Byte Count = X
ACK
ICS (Slave/Receiver)
Controller (Host)
X
Byt
e
ACK