FUJITSU F2MCTM-16LX User Manual
Page 118
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CHAPTER 5 CLOCKS
Table 5.4-1 Functional Description of Each Bit in the PLL/subclock Control Register (PSCCR)
Bit name
Function
bit15
to
bit12
Unused
These bits are not used.
Writing to these bits has no effect to operation.
Read value is always "1".
bit11
Reserved bit
Always write "0" to this bit.
Read value is always "1".
bit10 SCDS:
Subclock
division selection
bit
The division ratio of the subclock is selected.
When "0" is written to this bit, 4 division is selected.
When "1" is written to this bit, 2 division is selected.
Read value is always "1".
This bit is initialized to "0" by all reset causes.
bit9
Reserved bit
Always write "0" to this bit.
Read value is always "1".
bit8 CS2:
Multiplication
rate selection bit
This bit and CS1 and CS0 bits of the clock selection register (CKSCR) determine the PLL
multiplication rate.
CS2
CS1
CS0
PLL clock multiplication rate
0
0
0
Ч 1
0
0
1
Ч 2
0
1
0
Ч 3
0
1
1
Ч 4
1
1
0
Ч 6
1
1
1
Setting disabled
Read value is always "1".
This bit is initialized to "0" by all reset causes.
Note: When MCS or MCM bit is "0", setting CS2 to CS0 to "111
B
" is prohibited.
When CKSCR: CS1 and CS0 is set to "11
B
", do not set "1" to this bit.
Note: PSCCR register is write-only register. Read value is different from writing value. Do not use the RMW instruction
(SETB/CLRB instruction).