80C196KB USER’S GUIDE
INDIRECT REFERENCES
The indirect mode is used to access an operand by plac-
ing its address in a WORD variable in the register file.
The calculated address must conform to the alignment
rules for the operand type. Note that the indirect ad-
dress can refer to an operand anywhere within the ad-
dress space of the 80C196KB, including the register
file. The register which contains the indirect address is
selected by an eight bit field within the instruction. An
instruction can contain only one indirect reference and
the remaining operands of the instruction (if any) must
be register-direct references.
Examples
LD
AX,
[
AX
]
; AX:
4
MEM WORD(AX)
ADDB
AL,BL,
[
CX
]
; AL:
4
BL
0
MEM BYTE(CX)
POP
[
AX
]
; MEM WORD(AX):
4
MEM WORD(SP); SP:
4
SP
0
2
INDIRECT WITH AUTO-INCREMENT REFERENCES
This addressing mode is the same as the indirect mode
except that the WORD variable which contains the in-
direct address is incremented
after
it is used to address
the operand. If the instruction operates on BYTES or
SHORT-INTEGERS the indirect address variable will
be incremented by one. If the instruction operates on
WORDS or INTEGERS the indirect address variable
will be incremented by two.
Examples
LD
AX,
[
BX
]0
; AX:
4
MEM WORD(BX); BX:
4
BX
0
2
ADDB
AL,BL,
[
CX
]0
; AL:
4
BL
0
MEM BYTE(CX); CX:
4
CX
0
1
PUSH
[
AX
]0
; SP:
4
SP
1
2;
;
MEM WORD(SP):
4
MEM WORD(AX)
;
AX:
4
AX
0
2
IMMEDIATE REFERENCES
This addressing mode allows an operand to be taken
directly from a field in the instruction. For operations
on BYTE or SHORT-INTEGER operands this field is
eight
bits wide.
For
operations
on
WORD
or
INTEGER operands the field is 16 bits wide. An in-
struction can contain only one immediate reference and
the remaining operand(s) must be register-direct refer-
ences.
Examples
ADD
AX,
#
340 ; AX:
4
AX
0
340
PUSH
#
1234H
; SP:
4
SP
1
2; MEM WORD(SP):
4
1234H
DIVB AX,
#
10
; AL:
4
AX/10; AH:
4
AX MOD 10
SHORT-INDEXED REFERENCES
In this addressing mode an eight bit field in the instruc-
tion selects a WORD variable in the register file which
contains an address. A second eight bit field in the in-
struction stream is sign-extended and summed with the
WORD variable to form the address of the operand
which will take part in the calculation.
Since the eight bit field is sign-extended, the effective
address can be up to 128 bytes before the address in the
WORD variable and up to 127 bytes after it. An in-
struction can contain only one short-indexed reference
and the remaining operand(s) must be register-direct
references.
Examples
LD
AX,12
[
BX
]
; AX:
4
MEM WORD(BX
0
12)
MULB
AX,BL,3
[
CX
]
; AX:
4
BL*MEM BYTE(CX
0
3)
11
数控原理与维修
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in advance
Содержание 80C196KB Series
Страница 1: ...November 1990 80C196KB User s Guide Order Number 270651 003 http www agreenleaf cn...
Страница 59: ...80C196KB USER S GUIDE Figure 11 7 Ideal A D Characteristic 270651 37 55 http www agreenleaf cn...
Страница 60: ...80C196KB USER S GUIDE Figure 11 8 Actual and Ideal Characteristics 270651 38 56 http www agreenleaf cn...
Страница 61: ...80C196KB USER S GUIDE Figure 11 9 Terminal Based Characteristic 270651 39 57 http www agreenleaf cn...
Страница 70: ...80C196KB USER S GUIDE Figure 13 5 Reset Sequence 80C196KB Reset Sequence 270651 45 66 http www agreenleaf cn...
Страница 83: ...80C196KB USER S GUIDE 270651 80 Figure 15 14 AC Timing Diagrams 79 http www agreenleaf cn...
Страница 84: ...80C196KB USER S GUIDE 270651 81 270651 84 Figure 15 14 AC Timing Diagrams Continued 80 http www agreenleaf cn...