upd78f0730 Renesas Electronics Corporation., upd78f0730 Datasheet - Page 82

• Manufacturer Part Number: upd78f0730
• Description: 8-bit Single-chip Microcontroller
• Manufacturer: Renesas Electronics Corporation.

5.2 Configuration of Clock Generator
82
(3) USB clock
Remarks 1. f
The clock generator includes the following hardware.
Control registers
Oscillators
• PLL
This circuit multiplies the clock generated by the X1 oscillator (f
or 12.
Multiplication ratio x8 or x12 can be selected using the PLLM bit of the PLL control register (PLLC), and
operation of PLL is started or stopped by setting the PLLSTOP bit.
2. f
Item
X
EXCLK
:
:
X1 clock oscillation frequency
external main system clock frequency
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)
PLL control register (PLLC)
USB clock control register (UCKC)
X1 oscillator
Internal high-speed oscillator
Internal low-speed oscillator
Table 5-1. Configuration of Clock Generator
Preliminary User’s Manual U19014EJ1V0UD
CHAPTER 5 CLOCK GENERATOR
Configuration
X
) or external main system clock (f
EXCLK
) by 8