W83194R-39 Winbond, W83194R-39 Datasheet - Page 9

• Manufacturer Part Number: W83194R-39
• Description: 100MHZ 3-DIMM CLOCK
• Manufacturer: Winbond

Bytes sequence order for I
Set R/W to 1 when “r ead back ”, the data sequence is as follows :
8.3 SERIAL CONTROL REGISTERS
The Pin column lists the affected pin number and the @PowerUp column gives the default state at
true power up.
acknowledge of the Address Byte. Although the data (bits) in these two bytes are considered "don't
care", they must be sent and will be acknowledge.
(Register 0, Register 1, Register 2, ....) will be valid and acknowledged.
8.3.1 Register 0: CPU Frequency Select Register (default = 0)
Note : The frequency table selected by software via I
frequency table.
Bit
Clock Address
A(6:0) & R/W
Clock Address
A(6:0) & R/W
7
6
5
4
3
2
1
0
@PowerUp
0
0
0
0
0
0
0
0
"Command Code" byte and "Byte Count"
Ack
Ack
2
C controller :
8 bits dummy
Command code
Pin
-
-
-
-
-
-
-
-
Byte 0
0 = ¡Ó 0.25% Spread Spectrum Modulation
1 = ¡Ó 0.5% Spread Spectrum Modulation
SSEL2 (for frequency table selection by software via I
SSEL1 (for frequency table selection by software via I
SSEL0 (for frequency table selection by software via I
0 = Selection by hardware
1 = Selection by software I
SSEL3 (for frequency table selection by software via I
0 = Normal
1 = Spread Spectrum enabled
0 = Running
1 = Tristate all outputs
Ack
Ack
- 9 -
8 bits dummy
Byte count
Byte 1
After that, the below described sequence
2
C is the same as the hardware setting
Description
2
C - Bit 6:4
byte must be sent following the
Publication Release Date: May 1998
W83194R-39/-39A
Ack
Ack
Byte0,1,2...
until Stop
Byte2, 3, 4...
until Stop
PRELIMINARY
Revision 0.20
2
2
2
2
C)
C)
C)
C)