User manual

RL78/G1A CHAPTER 5 CLOCK GENERATOR
R01UH0305EJ0200 Rev.2.00 163
Jul 04, 2013
5.5 Clock Generator Operation
The clock generator generates the following clocks and controls the operation modes of the CPU, such as standby
mode (see Figure 5-1).
• Main system clock f
MAIN
• High-speed system clock f
MX
X1 clock fX
External main system clock f
EX
• High-speed on-chip oscillator clock f
IH
• Subsystem clock fSUB
• XT1 clock fXT
• External subsystem clock f
EXS
• Low-speed on-chip oscillator clock fIL
• CPU/peripheral hardware clock f
CLK
The CPU starts operation when the high-speed on-chip oscillator starts outputting after a reset release in the
RL78/G1A.
When the power supply voltage is turned on, the clock generator operation is shown in Figure 5-14.