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CHAPTER 3 CPU
3.7.1
Accumulator (A)
The accumulator (A) consists of two 16-bit arithmetic operation registers (AH and AL).
The accumulator is used to temporarily store the results of an arithmetic operation and
data.
The A register can be used as a 32-bit, 16-bit or 8-bit register. Various arithmetic
operations can be performed between memory and other registers or between the AH
register and the AL register. The A register has a data retention function that
automatically transfers pre-transfer data from the AL register to the AH register when
data of word length or less is transferred to the AL register. (Data is not retained with
some instructions.)
■
Accumulator (A)
●
Data transfer to the accumulator
The accumulator can process 32-bit (long word), 16-bit (word) and 8-bit (byte) data. The 4-bit data transfer
instruction (MOVN) is an exception. The explanation of 8-bit data also applies to 4-bit data.
•
For 32-bit data processing, the AH register and AL register are combined.
•
For 16-bit data and 8-bit data, only the AL register is used.
•
When data of byte length or less is transferred to the AL register, data becomes 16 bits long by sign
extension or zero extension, and is stored in the AL register. Data in the AL register can be handled as
word-length or byte-length data.
Figure 3.7-2 shows data transfer to the accumulator. Figure 3.7-3 to Figure 3.7-6 show specific transfer
examples.
Figure 3.7-2 Data Transfer to the Accumulator
3
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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: ......