Chapter 7 Clock Generator ( Μ Pd789860 Subseries); Clock Generator Functions; Clock Generator Configuration - NEC PD789860 User Manual

CHAPTER 7 CLOCK GENERATOR (

7.1 Clock Generator Functions

The clock generator generates the clock to be supplied to the CPU and peripheral hardware.
The following type of system clock oscillator is used.
• System clock (crystal/ceramic) oscillator
This circuit oscillates at 1.0 to 5.0 MHz. Oscillation can be stopped by executing the STOP instruction.

7.2 Clock Generator Configuration

The clock generator includes the following hardware.
Item
Control register
Oscillator
X1
System clock
oscillator
X2
STOP
Table 7-1. Configuration of Clock Generator
Processor clock control register (PCC)
Crystal/ceramic oscillator
Figure 7-1. Block Diagram of Clock Generator
Prescaler
f
X
f
X
2
2
Internal bus
User's Manual U14826EJ5V0UD
µ
PD789860 SUBSERIES)
Configuration
Prescaler
Standby
controller
PCC0
Processor clock control
register (PCC)
Clock to peripheral
hardware
Wait
CPU clock (f
controller
)
CPU
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