C8051F388-B Datasheet, PDF (141/285 Pages) Silicon Laboratories – Flash MCU Family

C8051F388/9/A/B
19.3. Clock Multiplier
The C8051F388/9/A/B device includes a 48 MHz high-frequency oscillator instead of a 12 MHz oscillator
and a 4x Clock Multiplier. For compatibility with C8051F34x and C8051F32x devices however, the CLK-
MUL register (SFR Definition 19.4) behaves as if the Clock Multiplier is present and working.
SFR Definition 19.4. CLKMUL: Clock Multiplier Control
Bit
7
6
5
4
3
2
Name MULEN MULINIT MULRDY
Type
R
R
R
R
R
R
Reset
1
1
1
0
0
0
SFR Address = 0xB9; SFR Page = 0
Bit
Name
Description
7
MULEN Clock Multiplier Enable Bit.
This bit always reads 1.
6
MULINIT Clock Multiplier Initialize Bit.
This bit always reads 1.
5 MULRDY Clock Multiplier Ready Bit.
This bit always reads 1.
4:2 Unused Read = 000b; Write = don’t care
1:0 MULSEL[1:0] Clock Multiplier Input Select Bits.
These bits always read 00.
1
0
MULSEL[1:0]
R
0
0
Rev. 1.1
141