Fujitsu FR81S User Manual
CHAPTER 5: CLOCK
4. Registers
FUJITSU SEMICONDUCTOR LIMITED
CHAPTER : CLOCK
FUJITSU SEMICONDUCTOR CONFIDENTIAL
24
[bit7 to bit4] POSW[3:0] (Pll clock OSc Wait) : PLL oscillation stabilization wait selection
These bits select the oscillation stabilization wait time for the PLL/SSCG clock (PLLSSCLK) as follows.
POSW[3:0]
PLL/SSCG clock oscillation
stabilization wait time
At 4MHz
At 8MHz
1000
2
9
×
main clock cycle
128.0[µs]
64.0[µs]
1001
2
10
×
main clock cycle
256.0[µs]
128.0[µs]
1010
2
11
×
main clock cycle
512.0[µs]
256.0[µs]
1011
2
12
×
main clock cycle
1024.0[µs]
512.0[µs]
1100
2
13
×
main clock cycle
2048.0[µs]
1024.0[µs]
1101
2
14
×
main clock cycle
4096.0[µs]
2048.0[µs]
1110
2
15
×
main clock cycle
8192.0[µs]
4096.0[µs]
1111
2
16
×
main clock cycle
(Initial value)
16384.0[µs]
8192.0[µs]
POSW3 always reads "1".
Note:
The PLL/SSCG clock lock up time wait time specification in this product is 200[μs]. Reserve the 200[μs] wait
time or more by either of the following methods.
⋅
Select 256[μs] POSW[3:0] or more.
⋅
Reserve the 200[μs] wait time or more by software processing, regardless of POSW[3:0] settings.
MB91520 Series
MN705-00010-1v0-E
185