
Si570/Si571
14
Rev. 0.31
4. Serial Port Registers
Note: Any register not listed here is reserved and must not be written. All bits are R/W unless otherwise noted.
Register
Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
7
High Speed/
N1 Dividers
HS_DIV[2:0]
N1[6:2]
8
Reference
Frequency
N1[1:0]
RFREQ[37:32]
9
Reference
Frequency
RFREQ[31:24]
10
Reference
Frequency
RFREQ[23:16]
11
Reference
Frequency
RFREQ[15:8]
12
Reference
Frequency
RFREQ[7:0]
135
Reset/Memory
Control
RST_REG NewFreq
RECALL
137
Freeze DCO
Freeze
DCO