CY28405 Cypress Semiconductor, CY28405 Datasheet - Page 5

• Manufacturer Part Number: CY28405
• Description: CK409-Compliant Clock Synthesizer
• Manufacturer: Cypress Semiconductor

Document #: 38-07512 Rev. *B
Table 4. Byte Read and Byte Write Protocol
Byte 0: Control Register 0
Byte 1: Control Register 1
Bit
Bit
11:18
20:27
7
6
5
4
3
2
1
0
7
6
5
4
3
2
1
0
2:8
Bit
10
19
28
29
1
9
@Pup
@Pup
Start
Slave address – 7 bits
Write = 0
Acknowledge from slave
Command Code – 8 bits
‘1xxxxxxx’ stands for byte operation, bits[6:0] of
the command code represents the offset of the
byte to be accessed
Acknowledge from slave
Data byte from master – 8 bits
Acknowledge from slave
Stop
HW
HW
HW
HW
HW
0
1
1
1
1
1
1
1
0
1
0
Byte Write Protocol
Reserved
Reserved
Reserved
Reserved
Reserved
CPUT_ITP, CPUC_ITP
CPUT1, CPUC1
CPUT0, CPUC0
PCIF
PCI
Reserved
FS_E
FS_D
FS_C
FS_B
FS_A
Description
Name
Name
Reserved, Set= 0
PCI Drive Strength Override
0 = Force All PCI and PCIF Outputs to Low Drive Strength
1= Force All PCI and PCIF Outputs to High Drive Strength
Reserved, Set= 0
Power up latched value of FS_E pin
Power up latched value of FS_D pin
Power up latched value of FS_C pin
Power up latched value of FS_B pin
Power up latched value of FS_A pin
Reserved, set = 0
Reserved, set = 1
Reserved, set = 1
Reserved, set = 1
Reserved, set = 1
CPUT/C_ITP Output Enable
0 = Disabled (three-state), 1 = Enabled
CPU(T/C)1 Output Enable,
0 = Disabled (three-state), 1 = Enabled
CPU(T/C)0 Output Enable
0 = Disabled (three-state), 1 = Enabled
21:27
30:37
11:18
Bit
2:8
10
19
20
28
29
38
39
1
9
Start
Slave address – 7 bits
Write = 0
Acknowledge from slave
Command Code – 8 bits
‘1xxxxxxx’ stands for byte operation, bits[6:0]
of the command code represents the offset of
the byte to be accessed
Acknowledge from slave
Repeat start
Slave address – 7 bits
Read = 1
Acknowledge from slave
Data byte from slave – 8 bits
Not Acknowledge
Stop
Description
Description
Byte Read Protocol
Description
CY28405
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