1989_MELPS_7700_Software_Manual

Absolute Indexed X
Mode
Function
Absolute indexed X addressing mode
The contents of the memory locations specified by a value resulting from addition of
a 16-bit numeric value expressed by the instruction's second and third bytes with the
contents of the index register X and the contents of the data bank register are the
actual data. If, however, addition of the numeric value expressed by the instruction's
second and third bytes with the contents of the index register X generates a carry,
the bank number will be 1 larger than the contents of the data bank register.
Instruction:
ADC,
LDY,
AND,
LSR,
ASL,
MPY,
CMP,
ORA,
DEC,
ROL,
DIV,
ROR,
EOR,
SBC,
INC,
STA
LDA,
LDM,
ex.
: Mnemonic
AOC A, OA012H, X
(m=1, x=1)
- - _
Memory
....
-------
Op Code (70,.)
Operand (12,.)
Operand (AD,.)
Machine Code
70'612'6 AO'6
Index
Register X
} + I i EE,·I=AEOO,.
ex.
: Mnemonic
AOC A, OA012H, X
(m=O, x=1)
Memory
("
1--------
Op Code (70,.)
Operand (12,.)
Operand (AD,.)
Machine Code
70'6 12'6 AO'6
Index
Register X
} + I : EE,J =AEOO,.
f-------
t-------
A-A+C+
r--------
1 DATA 1..,.- DATA
r-------­
-- '
Data Bank
Register
@!:jAEOO,.
A-A+C+
1 DATAl< i DATAL 1- {
-------
DATAL
DATAH
-
Data Bank
Register
@!J AEOO,.
31