MAIN problem select from the 12 operations which one to display on 7 segment

i am making a project of an 4 bit ALU on breadboards and ive prepared each operation on a separate board
i now want to input a 4 bit control input to choose the operation
i have thought about 2 ways either use 5(since i have 5 outputs) MUX(16 to 1) on the outputs
or use a decoder to choose which ciruit that will receive a vcc thus choosing which to operate
but the thing is they all output on the same 7 segment decoder

 

hi,

may i see some schematic diagram on that?

 

What do you mean that they all output on the same seven segment decoder?

I would not recommend power cycling the different portions of your ALU unless you have carefully considered the impact that doing so will have as far as inputs applied to those portions or the effect of the outputs from the unpowered sections.

I would recommend MUXing the outputs to select the one that is desired.

 

hi,

may i see some schematic diagram on that?