
52
CHAPTER 3 CPU
3.7.7
Program Counter (PC)
The program counter (PC) is a 16-bit counter that indicates the lower 16 bits of the
memory address of the next instruction code to be executed by the CPU.
■
Program Counter (PC)
The program bank register (PCB) specifies the upper 8 bits of the address where the next instruction code
to be executed by the CPU is stored. The PC specifies the lower 16 bits. Before being used, the actual
address is combined to become 24 bits, as shown in Figure 3.7-13.
The contents of the PC are updated by conditional branch instructions, subroutine call instructions,
interrupts and resets.
The PC can be used as a bus pointer for reading operands.
Figure 3.7-13 Program Counter (PC)
Note:
The PC and PCB cannot be rewritten directly by a program (such as by MOV PC and #FF).
Next instruction
to be executed
PCB
FE
H
PC
ABCD
H
FEABCD
H
Upper 8 bits Upper 16 bits
Содержание MB90460 Series
Страница 1: ...The following document contains information on Cypress products ...
Страница 3: ......
Страница 5: ......
Страница 9: ...iv ...
Страница 41: ...22 CHAPTER 1 OVERVIEW ...
Страница 45: ...26 CHAPTER 2 NOTES ON HANDLING DEVICES ...
Страница 83: ...64 CHAPTER 3 CPU ...
Страница 95: ...76 CHAPTER 4 RESET ...
Страница 107: ...88 CHAPTER 5 CLOCK ...
Страница 131: ...112 CHAPTER 6 LOW POWER CONSUMPTION MODE ...
Страница 175: ...156 CHAPTER 7 INTERRUPT ...
Страница 181: ...162 CHAPTER 8 MODE SETTING ...
Страница 223: ...204 CHAPTER 9 I O PORT ...
Страница 237: ...218 CHAPTER 10 TIME BASE TIMER ...
Страница 247: ...228 CHAPTER 11 WATCHDOG TIMER ...
Страница 275: ...256 CHAPTER 12 16 BIT RELOAD TIMER ...
Страница 373: ...354 CHAPTER 14 MULTI FUNCTIONAL TIMER ...
Страница 485: ...466 CHAPTER 16 PWC Timer ...
Страница 531: ...512 CHAPTER 17 UART ...
Страница 559: ...540 CHAPTER 19 DELAYED INTERRUPT GENERATOR MODULE ...
Страница 589: ...570 CHAPTER 20 8 10 BIT A D CONVERTER ...
Страница 601: ...582 CHAPTER 21 ROM CORRECTION FUNCTION ...
Страница 633: ...614 CHAPTER 23 512K 1024K BIT FLASH MEMORY ...
Страница 645: ...626 CHAPTER 24 EXAMPLE OF F2 MC 16LX MB90F462 F462A F463A CONNECTION FOR SERIAL WRITING ...
Страница 715: ...696 APPENDIX ...
Страница 716: ...697 INDEX INDEX The index follows on the next page This is listed in alphabetic order ...
Страница 739: ......