CY28401 Cypress Semiconductor, CY28401 Datasheet - Page 3

• Manufacturer Part Number: CY28401
• Description: 100-MHz Differential Buffer for PCI Express and SATA
• Manufacturer: Cypress Semiconductor

Document #: 38-07592 Rev. **
Table 2. Block Read and Block Write Protocol (continued)
Table 3. Byte Read and Byte Write Protocol
Byte 0: Control Register 0
20:27
11:18
Bit
20:27
29:36
38:45
11:18
Bit
2:8
10
19
28
29
7
6
5
4
1
9
Bit
19
28
37
46
....
....
....
....
Start
Slave address – 7 bits
Write = 0
Command Code – 8 bits
Stop
Acknowledge from slave
'100xxxxx' 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
@pup
Command Code – 8 bits
'00000000' stands for block operation
Acknowledge from slave
Byte Count from master – 8 bits
Acknowledge from slave
Data byte 0 from master – 8 bits
Acknowledge from slave
Data byte 1 from master – 8 bits
Acknowledge from slave
Data bytes from master/Acknowledge
Data Byte N – 8 bits
Acknowledge from slave
Stop
0
0
0
0
Block Write Protocol
Byte Write Protocol
Description
Description
Name
PWRDWN# drive mode
o = Driven when stopped, 1 = Three-state
SRC_STOP# drive mode
o = Driven when stopped, 1 = Three-state
Reserved
Reserved
21:27
30:37
39:46
48:55
11:18
Bit
19
20
28
29
38
47
56
....
....
....
....
11:18
21:27
30:37
2:8
Bit
10
19
20
28
29
38
39
1
9
Command Code – 8 bits
'00000000' stands for block operation
Acknowledge from slave
Repeat start
Slave address – 7 bits
Read = 1
Acknowledge from slave
Byte count from slave – 8 bits
Acknowledge from host
Data byte 0 from slave – 8 bits
Acknowledge from host
Data byte 1 from slave – 8 bits
Acknowledge from host
Data bytes from slave/Acknowledge
Data byte N from slave – 8 bits
Acknowledge from host
Stop
Start
Slave address – 7 bits
Write = 0
Acknowledge from slave
Command Code – 8 bits
'100xxxxx' 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
Acknowledge from master
Stop
Description
Block Read Protocol
Byte Read Protocol
Description
Description
CY28401
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