circuit harness wiring

Actually you can not bother to design a multiplexer using logic gates because it has many special IC which functioned for a multiplexer.

One of the TTL ICs from the family that you can use to fulfill the function of a multiplexer is IC 74 251. At the IC there are 8 input channels and 3-bit selector and the other lane as a control reset and inverting output. As a note if you are using TTL ICs for your electronic circuit, the voltage supply that is allowed a maximum of 5 volts. So you can be more familiar with the workings of this multiplexer ic, IC74251 consider the truth table below:

Despite the fact it is the family of TTL ICs that support more functions than the CMOS multiplexer. For the working principle of the multiplexer IC CMOS family is actually tantamount to a multiplexer circuit, or IC TTL logic gates. That should be all referring to the real multiplexer function, namely the determination of output lines which represent the number of input lines. The use of symbols is possible between TTL and CMOS IC has a different but actually run the same rules. For your reference if you are interested in using family of CMOS IC 4556 series in particular, I include also the truth table below: