COMMERCIALTEMPERATURERANGE

6

IDTCV109E

CLOCKGENERATORFORDESKTOPPCPLATFORMS

ONECYCLE™ INDEX BLOCK READ

Bit

# of bits

From

Description

1

1

Master

Start

2-9

8

Master

D2h

10

1

Slave

Acknowledge

11-18

8

Master

Registeroffsetbyte(startingbyte)

19

1

Slave

Acknowledge

20-27

8

Master

1xxxxxxx. Bit[20] = 1, followed with byte

count, which will be stored into SMBus table

byte 8.

28

1

Slave

Acknowledge

29

1

Master

Repeatedstart

30-37

8

Master

D3h

38

1

Slave

Acknowledge

39-46

8

Slave

Byte count, N, SMBus table byte 8 value.

Power on default is 0FH[15].

47

1

Master

Acknowledge

48-55

8

Slave

Offsetdatabyte,specifiedbybit[11:18]

56

1

Master

Acknowledge

57-64

8

Slave

Offset + 1 data byte

:

Slave

Offset + N-2

Master

Acknowledge

Slave

Offset + N-1

Notacknowledge

Stop

BYTE READ METHODS (CHOSE ONE):

• Use IDT OneCycle Index Block Read, bit[20:27] = 10000001.

Notice that byte count register (byte 8) will be changed to 0IH.

• Use Index Block Write protocol to change byte count (byte 8) to

1. After that, use Index Block Read.

TO CHANGE BYTE 8 VALUE:

• Use IDT OneCycle Index Block Read, as above

• Use Index Block Write protocol to change byte 8 value.

SMBUS PROTOCOL

INDEX BLOCK READ PROTOCOL

Bit

# of bits

From

Description

1

1

Master

Start

2-9

8

Master

D2h

10

1

Slave

Acknowledge

11-18

8

Master

Registeroffsetbyte(startingbyte)

19

1

Slave

Acknowledge

20

1

Master

Repeatedstart

21-28

8

Master

D3h

29

1

Slave

Acknowledge

30-37

8

Slave

Byte count, N, SMBus table byte 8 value.

Power on default is 0FH[15].

38

1

Master

Acknowledge

39-46

8

Slave

Offsetdatabyte,specifiedbybit11-18

47

1

Master

Acknowledge

48-55

8

Slave

Offset + 1 data byte

:

Slave

Offset + N-2

Master

Acknowledge

Slave

Offset + N-1

Notacknowledge

Stop

INDEX BLOCK WRITE PROTOCOL

Bit

# of bits

From

Description

1

1

Master

Start

2-9

8

Master

D2h

10

1

Slave

Acknowledge

11-18

8

Master

Registeroffsetbyte(startingbyte)

19

1

Slave

Acknowledge

20-27

8

Master

28

1

Slave

Acknowledge

29-36

8

Master

Firstdatabyte

37

1

Slave

Acknowledge

38-45

8

Master

Seconddatabyte

46

1

Slave

Acknowledge

:

Nth data byte

Stop

NOTE:

1. Bit [21:27] = byte count.

Bit 20 = 1, bit [21:27] will be stored into SMBus table, Byte 8. SM Bus Byte 8 is read

byte count register, power on default is 0FH.

Bit 20 = 0, normal SM bus operation.

BYTE WRITE METHODS:

• Setting bit[11:18] = starting address, bit [20:27] = 01H.