
Preliminary User’s Manual U19291EJ1V0UD
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4.2.7 Port 6...............................................................................................................................................132
4.2.8 Port 7...............................................................................................................................................133
4.2.9 Port 8...............................................................................................................................................138
4.2.10 Port 12...........................................................................................................................................141
4.2.11 Port 14...........................................................................................................................................145
4.2.12 Port 15...........................................................................................................................................147
4.3 Registers Controlling Port Function ........................................................................................ 149
4.4 Port Function Operations .......................................................................................................... 162
4.4.1 Writing to I/O port ............................................................................................................................162
4.4.2 Reading from I/O port......................................................................................................................162
4.4.3 Operations on I/O port.....................................................................................................................162
4.4.4 Connecting to external device with different power potential (2.5 V, 3 V)........................................163
4.5 Settings of Port Mode Register and Output Latch When Using Alternate Function........... 165
4.6 Cautions on 1-bit Manipulation Instruction for Port Register n (Pn) .................................... 168
CHAPTER 5 CLOCK GENERATOR .................................................................................................... 169
5.1 Functions of Clock Generator................................................................................................... 169
5.2 Configuration of Clock Generator ............................................................................................ 170
5.3 Registers Controlling Clock Generator.................................................................................... 172
5.4 System Clock Oscillator ............................................................................................................ 186
5.4.1 X1 oscillator.....................................................................................................................................186
5.4.2 XT1 oscillator ..................................................................................................................................186
5.4.3 Internal high-speed oscillator ..........................................................................................................190
5.4.4 20 MHz internal high-speed oscillator .............................................................................................190
5.4.5 Internal low-speed oscillator............................................................................................................190
5.4.6 Prescaler .........................................................................................................................................190
5.5 Clock Generator Operation ....................................................................................................... 191
5.6 Controlling Clock........................................................................................................................ 197
5.6.1 Example of controlling high-speed system clock .............................................................................197
5.6.2 Example of controlling internal high-speed oscillation clock............................................................200
5.6.3 Example of controlling subsystem clock..........................................................................................202
5.6.4 Example of controlling internal low-speed oscillation clock .............................................................204
5.6.5 CPU clock status transition diagram................................................................................................205
5.6.6 Condition before changing CPU clock and processing after changing CPU clock ..........................212
5.6.7 Time required for switchover of CPU clock and main system clock ................................................214
5.6.8 Conditions before clock oscillation is stopped .................................................................................215
CHAPTER 6 TIMER ARRAY UNIT TAUS .......................................................................................... 216
6.1 Functions of Timer Array Unit TAUS........................................................................................ 217
6.1.1 Functions of each channel when it operates independently ............................................................217
6.1.2 Functions of each channel when it operates with another channel .................................................218