Switching From X1 Input Clock To Subsystem Clock - NEC 78K0 User Manual

5.8.3 Switching from X1 input clock to subsystem clock

Figure 5-16. Switching from X1 Input Clock to Subsystem Clock (Flowchart)
X1 input
clock operation
Subsystem
clock
Note Set CSS to 1 after confirming that oscillation of the subsystem clock is stabilized.
CHAPTER 5 CLOCK GENERATOR
Register setting PCC.7 (MCC) = 0
in X1 input PCC.4 (CSS) = 0
clock operation
Subsystem clock operation
User's Manual U16227EJ2V0UD
; X1 oscillation
; X1 input clock or Ring-OSC clock
MCM = 03H ; X1 input clock operation
CSS ← 1
Note
; Subsystem clock operation
MCS = 1 not changed.
CLS is changed from 0 to 1.
121