
13
6.3 Port Function Control Registers...............................................................................................99
6.4 Operation of Port Functions ...................................................................................................103
6.4.1
Writing to I/O port ......................................................................................................................103
6.4.2
Reading from I/O port................................................................................................................103
6.4.3
Arithmetic operation of I/O port..................................................................................................103
CHAPTER 7 CLOCK GENERATION CIRCUIT (
μ
PD789197Y Subseries)............................................105
7.1 Clock Generation Circuit Functions.......................................................................................105
7.2 Clock Generation Circuit Configuration ................................................................................105
7.3 Registers Controlling Clock Generation Circuit ...................................................................107
7.4 System Clock Oscillators........................................................................................................110
7.4.1
Main system clock oscillator......................................................................................................110
7.4.2
Subsystem clock oscillator ........................................................................................................111
7.4.3
Scaler ........................................................................................................................................113
7.4.4
When no subsystem clocks are used........................................................................................113
7.5 Clock Generation Circuit Operation.......................................................................................114
7.6 Changing Setting of System Clock and CPU Clock..............................................................115
7.6.1
Time required for switching between system clock and CPU clock ..........................................115
7.6.2
Switching between system clock and CPU clock......................................................................116
CHAPTER 8 CLOCK GENERATION CIRCUIT (
μ
PD789217Y Subseries)............................................117
8.1 Clock Generation Circuit Functions.......................................................................................117
8.2 Clock Generation Circuit Configuration ................................................................................117
8.3 Registers Controlling Clock Generation Circuit ...................................................................119
8.4 System Clock Oscillators........................................................................................................122
8.4.1
Main system clock oscillator......................................................................................................122
8.4.2
Subsystem clock oscillator ........................................................................................................123
8.4.3
Scaler ........................................................................................................................................127
8.4.4
When no subsystem clocks are used........................................................................................127
8.5 Clock Generation Circuit Operation.......................................................................................128
8.6 Changing Setting of System Clock and CPU Clock..............................................................129
8.6.1
Time required for switching between system clock and CPU clock ..........................................129
8.6.2
Switching between system clock and CPU clock......................................................................130
CHAPTER 9 16-BIT TIMER COUNTER ..................................................................................................131
9.1 16-Bit Timer Counter Functions .............................................................................................132
9.2 16-Bit Timer Counter Configuration.......................................................................................133
9.3 Registers Controlling 16-Bit Timer Counter..........................................................................136
9.4 16-Bit Timer Counter Operation..............................................................................................140
9.4.1
Operation as timer interrupt.......................................................................................................140
9.4.2
Operation as timer output..........................................................................................................142
9.4.3
Capture operation......................................................................................................................143
9.4.4
16-bit timer 90 readout ..............................................................................................................144
9.4.5
Buzzer output operation ............................................................................................................145