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ICS9248- 39

1.

The ICS clock generator is a slave/receiver, I

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

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

The information in this section assumes familiarity with I

For more information, contact ICS for an I

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.

• Controller (host) sends a Stop bit

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

• Controller (host) will send a stop bit

Notes:

Controller (Host)

ICS (Slave/Receiver)

Start Bit

Address

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

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: