3
ICS951601
Preliminary Prouct Preview
0663C—10/04/05
1.
The ICS clock generator is a slave/receiver, I
2C component.It can read back the data stored in the latches
for verification. Read-Back will support Intel PIIX4 "Block-Read" protocol.
2.
The data transfer rate supported by this clock generator is 100K bits/sec or less (standard mode)
3.
The input is operating at 3.3V logic levels.
4.
The data byte format is 8 bit bytes.
5.
To simplify the clock generator I
2C interface, the protocol is set to use only "Block-Writes" from the
controller.The bytes must be accessed in sequential order from lowest to highest byte with the ability to
stop after any complete byte has been transferred. The Command code and Byte count shown above
must be sent, but the data is ignored for those two bytes. The data is loaded until a Stop sequence is
issued.
6.
At power-on, all registers are set to a default condition, as shown.
General I
2C serial interface information
The information in this section assumes familiarity with I
2C programming.
How to Write:
Controller (host) sends a start bit.
Controller (host) sends the write address D2
(H)
ICS clock will
acknowledge
Controller (host) sends a dummy command code
ICS clock will
acknowledge
Controller (host) sends a dummy byte count
ICS clock will
acknowledge
Controller (host) starts sending first byte (Byte 0)
through byte 5
ICS clock will
acknowledge each byte one at a
time.
How to Read:
Controller (host) will send start bit.
Controller (host) sends the read address D3
(H)
ICS clock will
acknowledge
ICS clock will send the
byte count
Controller (host) acknowledges
ICS clock sends first byte
(Byte 0) through byte
5
Controller (host) will need to acknowledge each
byte
Notes:
Controller (Host)
ICS (Slave/Receiver)
Start Bit
Address
D3(H)
ACK
Byte Count
ACK
Byte 0
ACK
Byte 1
ACK
Byte 2
ACK
Byte 3
ACK
Byte 4
ACK
Byte 5
ACK
Stop Bit
How to Read:
Controller (Host)
ICS (Slave/Receiver)
Start Bit
Address
D2(H)
ACK
Dummy Command Code
ACK
Dummy Byte Count
ACK
Byte 0
ACK
Byte 1
ACK
Byte 2
ACK
Byte 3
ACK
Byte 4
ACK
Byte 5
ACK
Stop Bit
How to Write: