C-5
INSTRUCTION SET DESCRIPTIONS
AAS
ASCII Adjust for Subtraction:
AAS
Corrects the result of a previous
subtraction of two valid unpacked
decimal operands (the destination
operand must have been specified as
register AL). Changes the content of
AL to a valid unpacked decimal
number; the high-order half-byte is
zeroed.
Instruction Operands:
none
if
((AL) and 0FH) > 9 or (AF) = 1
then
(AL)
←
(AL) – 6
(AH)
←
(AH) – 1
(AF)
←
1
(CF)
←
(AF)
(AL)
←
(AL) and 0FH
AF
ü
CF
ü
DF –
IF –
OF ?
PF ?
SF ?
TF –
ZF ?
ADC
Add with Carry:
ADC dest, src
Sums the operands, which may be
bytes or words, adds one if CF is set
and replaces the destination operand
with the result. Both operands may be
signed or unsigned binary numbers
(see AAA and DAA). Since ADC incor-
porates a carry from a previous
operation, it can be used to write
routines to add numbers longer than
16 bits.
Instruction Operands:
ADC reg, reg
ADC reg, mem
ADC mem, reg
ADC reg, immed
ADC mem, immed
ADC accum, immed
if
(CF) = 1
then
(dest)
←
(dest) + (src) + 1
else
(dest)
←
(dest) + (src)
AF
ü
CF
ü
DF –
IF –
OF
ü
PF
ü
SF
ü
TF –
ZF
ü
Table C-4. Instruction Set (Continued)
Name
Description
Operation
Flags
Affected
NOTE:
The three symbols used in the Flags Affected column are defined as follows:
– the contents of the flag remain unchanged after the instruction is executed
? the contents of the flag is undefined after the instruction is executed
ü
the flag is updated after the instruction is executed
Содержание 80C186XL
Страница 1: ...80C186XL 80C188XL Microprocessor User s Manual...
Страница 2: ...80C186XL 80C188XL Microprocessor User s Manual 1995...
Страница 18: ...1 Introduction...
Страница 19: ......
Страница 27: ......
Страница 28: ...2 Overview of the 80C186 Family Architecture...
Страница 29: ......
Страница 79: ......
Страница 80: ...3 Bus Interface Unit...
Страница 81: ......
Страница 127: ......
Страница 128: ...4 Peripheral Control Block...
Страница 129: ......
Страница 137: ......
Страница 138: ...5 ClockGenerationand Power Management...
Страница 139: ......
Страница 154: ...6 Chip Select Unit...
Страница 155: ......
Страница 178: ...7 Refresh Control Unit...
Страница 179: ......
Страница 193: ......
Страница 194: ...8 Interrupt Control Unit...
Страница 195: ......
Страница 227: ......
Страница 228: ...9 Timer Counter Unit...
Страница 229: ......
Страница 253: ......
Страница 254: ...10 Direct Memory Access Unit...
Страница 255: ......
Страница 283: ......
Страница 284: ...11 Math Coprocessing...
Страница 285: ......
Страница 302: ...12 ONCE Mode...
Страница 303: ......
Страница 306: ...A 80C186 Instruction Set Additions and Extensions...
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Страница 318: ...B Input Synchronization...
Страница 319: ......
Страница 322: ...C Instruction Set Descriptions...
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Страница 371: ......
Страница 372: ...D Instruction Set Opcodes and Clock Cycles...
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Страница 396: ...Index...
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