UPD78F0411GA-GAM-AX Datasheet, PDF (109/564 Pages) Renesas Technology Corp – Old Company Name in Catalogs and Other Documents

CHAPTER 5 CLOCK GENERATOR
(3) Internal low-speed oscillation clock (clock for watchdog timer)
• Internal low-speed oscillator
This circuit oscillates a clock of fRL = 240 kHz (TYP.). After a reset release, the internal low-speed oscillation
clock always starts operating.
Oscillation can be stopped by using the internal oscillation mode register (RCM) when “internal low-speed
oscillator can be stopped by software” is set by option byte.
The internal low-speed oscillation clock cannot be used as the CPU clock. The following hardware operates
with the internal low-speed oscillation clock.
• Watchdog timer
• 8-bit timer H1 (if fRL, fRL/2⁷ or fRL/2⁹ is selected as the count clock)
• LCD controller/driver (if fRL/2³ is selected as the LCD source clock)
Remark fRL: Internal low-speed oscillation clock frequency
5.2 Configuration of Clock Generator
The clock generator includes the following hardware.
Item
Control registers
Oscillators
Table 5-1. Configuration of Clock Generator
Configuration
Clock operation mode select register (OSCCTL)
Processor clock control register (PCC)
Internal oscillation mode register (RCM)
Main OSC control register (MOC)
Main clock mode register (MCM)
Oscillation stabilization time counter status register (OSTC)
Oscillation stabilization time select register (OSTS)
Internal high-speed oscillation trimming register (HIOTRM)
X1 oscillator
XT1 oscillator
Internal high-speed oscillator
Internal low-speed oscillator
User’s Manual U18698EJ1V0UD
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