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Noopi
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Homework Statement
Make a BCD 3321 encoder. So if you input 0100, the encoder will output (depending on your design) either a 1001, or a 0101. Similarly, an input of 0101 will output either a 1010 or a 0110 (again, depending on your design).
Homework Equations
I know you're supposed to use DeMorgan's Law, but I have a hard time understanding WHEN to use it.
The Attempt at a Solution
I have done the truth table, the kmaps, and derived the logical expressions for each bit, but what I'm having a hard time doing is turning my AND-OR logic expressions into NAND-NAND logic expressions.
My 4 logical expressions are:
(3) MSB: A + BC
(3) Second MSB: A + B + CD
(2) Third MSB: A + BC'D + B'CD'
(1) LSB: BCD + BC'D' + B'C'D
My professor mentioned something about double negating the equations, and then applying DeMorgan's Law to get the NAND-NAND logic, and that's where he lost me.
Any help will be greatly appreciated!