User’s Manual U14826EJ5V0UD
12
7.5
Clock Generator Operation .......................................................................................................74
7.6
Changing Setting of CPU Clock................................................................................................75
7.6.1
Time required for switching CPU clock ........................................................................................75
7.6.2 Switching CPU clock ...................................................................................................................75
CHAPTER 8 CLOCK GENERATOR (
µ
PD789861 SUBSERIES)........................................................76
8.1
Clock Generator Functions .......................................................................................................76
8.2
Clock Generator Configuration ................................................................................................76
8.3
Clock Generator Control Register............................................................................................77
8.4 System
Clock
Oscillators ..........................................................................................................78
8.4.1 System
clock oscillator ................................................................................................................78
8.4.2
Examples of incorrect resonator connection................................................................................79
8.4.3 Frequency divider ........................................................................................................................80
8.5
Clock Generator Operation .......................................................................................................81
8.6
Changing Setting of CPU Clock................................................................................................82
8.6.1
Time required for switching CPU clock ........................................................................................82
8.6.2 Switching CPU clock ...................................................................................................................82
CHAPTER 9 8-BIT TIMERS 30 AND 40..............................................................................................83
9.1
8-Bit Timers 30, 40 Functions ...................................................................................................83
9.2
8-Bit Timers 30, 40 Configuration.............................................................................................84
9.3
8-Bit Timers 30, 40 Control Registers ......................................................................................88
9.4
8-Bit Timers 30, 40 Operation ...................................................................................................93
9.4.1 Operation
as
8-bit timer counter ..................................................................................................93
9.4.2 Operation
as
16-bit timer counter .............................................................................................. 102
9.4.3 Operation
as carrier generator................................................................................................... 109
9.4.4
Operation as PWM output (timer 40 only).................................................................................. 114
9.5
Notes on Using 8-Bit Timers 30, 40 ........................................................................................116
CHAPTER 10 WATCHDOG TIMER .....................................................................................................118
10.1 Watchdog Timer Functions.....................................................................................................118
10.2 Watchdog Timer Configuration ..............................................................................................119
10.3 Watchdog Timer Control Registers........................................................................................120
10.4 Watchdog Timer Operation .....................................................................................................122
10.4.1 Operation
as watchdog timer..................................................................................................... 122
10.4.2 Operation
as
interval timer......................................................................................................... 123
CHAPTER 11 POWER-ON-CLEAR CIRCUITS ...................................................................................124
11.1 Power-on-Clear Circuit Functions ..........................................................................................124
11.2 Power-on-Clear Circuit Configuration ...................................................................................124
11.3 Power-on-Clear Circuit Control Registers.............................................................................126
11.4 Power-on-Clear Circuit Operation ..........................................................................................128
11.4.1 Power-on-clear
(POC) circuit operation ..................................................................................... 128
11.4.2
Operation of low-voltage detection (LVI) circuit ......................................................................... 130