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WEEK THREELearning outcome for this week Review the work of a pass assembler Basic Assembly Functions Assembler directives An Assembler example program Teachers Activities Outline i Basic assembler functions ii)
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simple SIC assembler example Page | 19 BASIC ASSEMBLER FUNCTIONS Translating mnemonic operation codes to their machine language equivalents Assigning machine addresses to symbolic labels
Figure 3.1 Basic Assembler Functions OTHER FUNCTIONS INCLUDE •
Converting mnemonic operation codes to their machine language equivalents Converting symbolic operands to their equivalent machine addresses Deciding the proper instruction format Converting the data constants to internal machine representations Writing the object program and the assembly
listing ASSEMBLER DIRECTIVES •
Assembler directives are pseudo instructions They provide instructions to the assembler itself They are not translated into machine operation codes Example for SIC assembler directive
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START : specify name &
starting address •
END : end of source program, specify the
first execution instruction •
BYTE, WORD, RESB, RESW
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End of record : a null char (00)
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End of file : a zero- length record
NOTE: This program example will be theoretically explained in the class and further used Share with your friends: