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User’s Manual U17473EJ2V0UD
15
CHAPTER 21 KEY INTERRUPT FUNCTION......................................................................................................................... 537
21.1 Functions of Key Interrupt ...................................................................................................... 537
21.2 Configuration of Key Interrupt................................................................................................ 537
21.3 Register Controlling Key Interrupt ......................................................................................... 538
CHAPTER 22 STANDBY FUNCTION....................................................................................................................................... 539
22.1 Standby Function and Configuration..................................................................................... 539
22.1.1 Standby function ..........................................................................................................................539
22.1.2 Registers controlling standby function .........................................................................................539
22.2 Standby Function Operation................................................................................................... 542
22.2.1 HALT mode..................................................................................................................................542
22.2.2 STOP mode .................................................................................................................................547
CHAPTER 23 RESET FUNCTION ............................................................................................................................................. 552
23.1 Register for Confirming Reset Source................................................................................... 560
CHAPTER 24 POWER-ON-CLEAR CIRCUIT......................................................................................................................... 561
24.1 Functions of Power-on-Clear Circuit ..................................................................................... 561
24.2 Configuration of Power-on-Clear Circuit ............................................................................... 562
24.3 Operation of Power-on-Clear Circuit...................................................................................... 562
24.4 Cautions for Power-on-Clear Circuit ...................................................................................... 565
CHAPTER 25 LOW-VOLTAGE DETECTOR.......................................................................................................................... 567
25.1 Functions of Low-Voltage Detector ....................................................................................... 567
25.2 Configuration of Low-Voltage Detector ................................................................................. 568
25.3 Registers Controlling Low-Voltage Detector ........................................................................ 568
25.4 Operation of Low-Voltage Detector........................................................................................ 571
25.4.1 When used as reset .....................................................................................................................572
25.4.2 When used as interrupt................................................................................................................577
25.5 Cautions for Low-Voltage Detector ........................................................................................ 582
CHAPTER 26 OPTION BYTE...................................................................................................................................................... 585
26.1
Functions of Option Bytes .................................................................................................... 585
26.2
Format of Option Byte ........................................................................................................... 587
CHAPTER 27 FLASH MEMORY................................................................................................................................................ 590
27.1 Internal Memory Size Switching Register.............................................................................. 590
27.2 Internal Expansion RAM Size Switching Register ................................................................ 591
27.3 Writing with Flash Programmer.............................................................................................. 592
27.4 Programming Environment..................................................................................................... 598
27.5 Communication Mode.............................................................................................................. 598
27.6 Handling of Pins on Board ...................................................................................................... 600
27.6.1 FLMD0 pin ...................................................................................................................................600
27.6.2 Serial interface pins .....................................................................................................................600
27.6.3 RESET pin ...................................................................................................................................602
27.6.4 Port pins.......................................................................................................................................602
27.6.5 REGC pin.....................................................................................................................................602
27.6.6 Other signal pins ..........................................................................................................................602
27.6.7 Power supply ...............................................................................................................................603