
CY28378
........................ Document #: 38-07519 Rev. ** Page 6 of 21
Byte Configuration Map
Table 5. 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
Bit
@Pup
Name
Description
Bit 7
0
Spread Select2
‘000’ = OFF
‘001’ = +0.12, – 0.62%
‘010’ = +0.25, – 0.75%
‘011’ = +0.50, – 1.00%
‘100’ = ± 0.25%
‘101’ = +0.00, – 0.50%
‘110’ = ±0.5%
‘111’ = ±0.38%
Bit 6
0
Spread Select1
Bit 5
0
Spread Select0
Bit 4
0
SEL4
SW Frequency selection bits. See
Table 2.Bit 3
0
SEL3
Bit 2
0
SEL2
Bit 1
0
SEL1
Bit 0
0
SEL0
Byte 1
Bit
@Pup
Name
Description
Bit 7
1
CPUT1, CPUC1
(Active/Inactive)
Bit 6
1
CPUT0, CPUC0
Bit 5
1
48MHz
(Active/Inactive)
Bit 4
1
24_48MHz
(Active/Inactive)
Bit 3
1
3V66_3
(Active/Inactive)
Bit 2
1
3V66_2
(Active/Inactive)
Bit 1
1
3V66_1
(Active/Inactive)
Bit 0
1
3V66_0
(Active/Inactive)