A - 6
18. Flash Memory
245
18.1
Overview .................................................................................................245
18.2
Memory Map ...........................................................................................247
18.3
Functions to Prevent Rewriting of Flash Memory....................................249
18.3.1
ID Code Check Function ..................................................................249
18.3.2
ROM Code Protect Function ............................................................250
18.4
CPU Rewrite Mode..................................................................................251
18.4.1
EW0 Mode........................................................................................252
18.4.2
EW1 Mode........................................................................................252
18.4.3
Software Commands ........................................................................261
18.4.4
Status Register .................................................................................266
18.4.5
Full Status Check .............................................................................267
18.5
Standard Serial I/O Mode........................................................................269
18.5.1
ID Code Check Function ..................................................................269
18.6
Parallel I/O Mode.....................................................................................273
18.6.1
ROM Code Protect Function ............................................................273
18.7
Notes on Flash Memory ..........................................................................274
18.7.1
CPU Rewrite Mode...........................................................................274
19. Electrical Characteristics
276
20. Usage Notes
296
20.1
Notes on Clock Generation Circuit ..........................................................296
20.1.1
Stop Mode ........................................................................................296
20.1.2
Wait Mode ........................................................................................296
20.1.3
Oscillation Stop Detection Function..................................................296
20.1.4
Oscillation Circuit Constants.............................................................296
20.1.5
High-Speed On-Chip Oscillator Clock ..............................................296
20.2
Notes on Interrupts..................................................................................297
20.2.1
Reading Address 00000h .................................................................297
20.2.2
SP Setting.........................................................................................297
20.2.3
External Interrupt and Key Input Interrupt ........................................297
20.2.4
Watchdog Timer Interrupt.................................................................297
20.2.5
Changing Interrupt Sources..............................................................298
20.2.6
Changing Interrupt Control Register Contents .................................299
20.3
Precautions on Timers ............................................................................300