Si5345-44-42-D-RM
80
Rev. 1.0
14.2. Register Map Overview and Default Settings Values
The Si5345/44/42 family has a large register map and is divided into separate pages. Each page contains a total of
256 registers, although all 256 registers are not used. Register 1 on each page is reserved to indicate the page and
register 0x00FE is reserved for the device ready status. The following is a summary of the content that can be
found on each of the pages. Note any page that is not listed is not used for the device. Do not attempt to write to
registers that have not been described in this document, even if they are accessible. Note that the default value will
depend on the values loaded into NVM, which is determined by the part number.
Where not provided in the register map information below, you can get the default values of the regiister map
settings by accessing the part number lookup utility at:
www.silabs.com/products/clocksoscillators/clock-generator/Pages/clockbuilder-lookup.aspx
Register map settings values are listed in the datasheet addendum, which can also be accessed by using the link
above.The register maps are broken out for the Si5345, Si5344, and Si5342 separately.
R = Read Only
R/W = Read Write
S = Self Clearing
Registers that are sticky are cleared by writing “0” to the bits that have been set in hardware. A self-clearing bit will
clear on its own when the state has changed.
Table 45. Register Map Paging Descriptions
Page
Start Address
(Hex)
Start Address
(Decimal)
Contents
Page 0
0000h
0
Alarms, interrupts, reset, other configuration
Page 1
0100h
256
Clock output configuration
Page 2
0200h
512
P,R dividers, scratch area
Page 3
0300h
768
Output N dividers, N divider Finc/Fdec
Page 4
0400h
1024
ZD mode configuration
Page 5
0500h
1280
M divider, BW, holdover, input switch, FINC/DEC
Page 9
0900h
2304
Control IO configuration