Programming instructions

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Multisim Component Reference Guide 6-40 ni.com
6.4.70 74xx20 (Dual 4-In NAND)
This device contains two independent 4-input NAND gates.
Logic function:
NAND gate truth table
6.4.71 74xx21 (Dual 4-In AND)
This device contains two independent 4-input AND gates.
Logic function:
AND gate truth table:
Y = ABCD
ABCDY
11110
0XXX1
X0XX1
XX0X1
XXX01
Y = ABCD
ABCDY
11111
0XXX0
X0XX0
XX0X0
XXX00
ComponentRef.book Page 40 Thursday, December 7, 2006 10:12 AM