50 lines
907 B
Plaintext
50 lines
907 B
Plaintext
BEGIN HEADER
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A 3-bit decoder design using Truth Table entry. Test vector
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block is included for simulation.
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Copyright National Semiconductor Corp, 1992.
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END HEADER
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BEGIN DEFINITION
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DEVICE p16l8;
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INPUTS a[15:13]=[2:4];
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OUTPUTS (COM) /o[0:7]=[12:19];
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SET DECODE_IN = a[15:13];
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END DEFINITION
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BEGIN TRUTH_TABLE
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TTIN a15,a14,a13;
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TTOUT /o0, /o1, /o2, /o3, /o4, /o5, /o6, /o7;
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000 10000000
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001 01000000
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010 00100000
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011 00010000
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100 00001000
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101 00000100
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110 00000010
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111 00000001
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END TRUTH_TABLE
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begin vector
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a15,a14,a13,/o0,/o1,/o2,/o3,/o4,/o5,/o6,/o7;
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PROBE DECODE_IN ; { Observe a15,14,13 as a bus signal }
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000 HLLLLLLL
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001 LHLLLLLL
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010 LLHLLLLL
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011 LLLHLLLL
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100 LLLLHLLL
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101 LLLLLHLL
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110 LLLLLLHL
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111 LLLLLLLH
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110 LLLLLLHL
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101 LLLLLHLL
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100 LLLLHLLL
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011 LLLHLLLL
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010 LLHLLLLL
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001 LHLLLLLL
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000 HLLLLLLL
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end vector
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