Switching From High-Speed System Clock To Ring-Osc Clock - NEC MuPD78F0132H User Manual

5.8.2 Switching from high-speed system clock to Ring-OSC clock

Figure 5-15. Switching from High-Speed System Clock to Ring-OSC Clock (Flowchart)
Register setting
in high-speed system
clock operation
High-speed
system clock
operation
Ring-OSC
clock operation
Note Required only when "can be stopped by software" is selected for Ring-OSC by the option byte.
132
CHAPTER 5 CLOCK GENERATOR
PCC.7 (MCC) = 0
PCC.4 (CSS) = 0
MCM = 03H
Yes: RSTOP = 1
RCM.0
(RSTOP) = 1?
RSTOP = 0
MCM.0 ← 0
Ring-OSC clock operation
User's Manual U16899EJ2V0UD
; High-speed system clock oscillation
; High-speed system clock or Ring-OSC clock
; High-speed system clock operation
Note
; Ring-OSC oscillating?
No: RSTOP = 0
; Ring-OSC oscillating
MCM.1 (MCS) is changed from 1 to 0