https://en.wikipedia.org/wiki/Binary_decoder
Use in a switch to detect and use the off position
Chips
SN7404 Hex Invertor
SN7414
SN7408 Quad AND gate
or SN74138 3-Line To 8-Line Decoders/Demultiplexers
Test Platform
Using pure logic
Using a 74138 decoder per switch
adding pull down to the switches