Cypress CY25822-2 User Manual
Page 3
CY25822-2
Document #: 38-07531 Rev. **
Page 3 of 9
....
Data Byte N –8 bits
56
Acknowledge
....
Acknowledge from slave
....
Data bytes from slave/Acknowledge
....
Stop
....
Data byte N from slave – 8 bits
....
Not Acknowledge
....
Stop
Table 2. Block Read and Block Write Protocol (continued)
Table 3. Byte Read and Byte Write Protocol
Byte Write Protocol
Byte Read Protocol
Bit
Description
Bit
Description
1
Start
1
Start
2:8
Slave address – 7 bits
2:8
Slave address – 7 bits
9
Write = 0
9
Write = 0
10
Acknowledge from slave
10
Acknowledge from slave
11:18
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
11:18
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
19
Acknowledge from slave
19
Acknowledge from slave
20:27
Data byte from master – 8 bits
20
Repeat start
28
Acknowledge from slave
21:27
Slave address – 7 bits
29
Stop
28
Read = 1
29
Acknowledge from slave
30:37
Data byte from slave – 8 bits
38
Not Acknowledge
39
Stop
Byte 0: Control Register
Bit
@Pup
Pin#
Name
Pin Description
7
1
4
SS0
–
6
0
4
SS1
–
5
0
4
SS2
–
4
0
4
SS3
–
3
1
Not Applicable
Reserved, must be written as 1
2
1
4, 5
CLKOUT,
REFOUT
Power-down three-state enable
0 = three-state outputs, 1 = drive outputs low
(Applies only in Power Down State)
1
1
4
CLKOUT
Spread Spectrum enable
0 = spread off, 1 = spread on
0
0
Not Applicable
No Pins
Table 4. Spread Spectrum Select
SS3
SS2
SS1
SS0
Spread Mode
Spread Amount%
0
0
0
0
Down
0.8
0
0
0
1
Down
1.0
0
0
1
0
Down
1.25
0
0
1
1
Down
1.5
0
1
0
0
Down
1.75