Assemble the following code segment (use Appendix A1 in the book). Note that some rows in the machine code column may contain more than one byte, and some rows may have no machine code. Specify the address for each instruction op-code in the LOCATION column. Do not forget the $-sign for hex numbers. Note: ‘ORG $C000’ is an assembler directive that sets the address for the opcode of the instruction immediately following the ORG statement to $C000. Assembler directives do not produce any machine code. Indicate the addressing mode of each instruction in the appropriate column. ADDRESS MODE LOCATION MACHINE CODE
ORG $C000
$C000 LDX #$000C
LDY $0C
LDY 1, Y
LDAA 1,X
LDAB 1, Y
SBA
Hand execute the above program assuming the initial processor conditions below. In each row, please fill in the contents of the registers AFTER the fetch and execution of the corresponding instruction. Assume the following memory model. Do not forget the $-sign for hex numbers.
LOCATION DATA
$000A $00
$000B $0C
$000C $00
$000D $0D
$000E $00
$000F $0A
STEP # PC X Y A B
Before exec. $C000 $ $ 00 00
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