Renesas RL78/G10 User Manual

RL78/G10 CHAPTER 5 CLOCK GENERATOR
R01UH0384EJ0311 Rev. 3.11 98
Dec 22, 2016
5.6.4 Condition before changing CPU clock and processing after changing CPU clock
Condition before changing the CPU clock and processing after changing the CPU clock are shown below.
Table 5-4. Changing CPU Clock
CPU Clock
Condition Before Change Processing After Change
Before Change After Change
High-speed on-
chip oscillator
clock
X1 clock
Stabilization of X1 oscillation
• OSCSEL = 1, EXCLK = 0, MSTOP = 0
• After elapse of oscillation stabilization time
The operating current can be reduced by
stopping the high-speed on-chip oscillator
(HIOSTOP = 1) after checking that the CPU
clock is changed.
External main
system clock
An external clock input from the EXCLK pin
must be enabled.
• OSCSEL = 1, EXCLK = 1, MSTOP = 0
X1 clock
High-speed on-
chip oscillator
clock
Enabling oscillation of high-speed on-chip
oscillator
• HIOSTOP = 0
• After elapse of oscillation accuracy
stabilization time
X1 oscillation can be stopped (MSTOP = 1)
after checking that the CPU clock is changed.
External main
system clock
Change is not possible
−
External main
system clock
High-speed on-
chip oscillator
clock
Enabling oscillation of high-speed on-chip
oscillator
• HIOSTOP = 0
• After elapse of oscillation accuracy
stabilization time
External main system clock input can be
disabled (MSTOP = 1) after checking that the
CPU clock is changed.
X1 clock Change is not possible
−

Renesas RL78/G10 Specifications

General

Brand	Renesas
Model	RL78/G10
Category	Motherboard
Language	English