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Board NEDONAND-7

A project log for NEDONAND homebrew computer

NEDONAND is 8-bit homebrew computer entirely built out of many 74F00 chips (2-input NAND gates)

SHAOSSHAOS 02/28/2016 at 06:410 Comments

Board NEDONAND-7 implements demultiplexer 1:8 with active "1":

Input EN is also inverted and going out as /ENO for cascading. Board was already ordered through OSHPark:

Pins description:

1) GND - ground
2) O0 - output "1" if EN="1" and A=0
3) O1 - output "1" if EN="1" and A=1
4) O2 - output "1" if EN="1" and A=2
5) O3 - output "1" if EN="1" and A=3
6) O4 - output "1" if EN="1" and A=4
7) O5 - output "1" if EN="1" and A=5
8) O6 - output "1" if EN="1" and A=6
9) O7 - output "1" if EN="1" and A=7
10)/ENO - output of inverted EN
11)EN - enable input (must be "1" to demultiplex)
12)VCC - power +5V
13)GND - another ground
14)A0 - bit 0 of address
15)A1 - bit 1 of address
16)A2 - bit 2 of address

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