Lesson 2

The next component selects between two control buses.

Problem. Synthesize a circuit of size \(5\) over \(\{\operatorname{NAND}_{2}, \operatorname{SELECT}_{1}, \operatorname{SELECT}_{16}\}\) computing the control-selector function: \[\begin{aligned}\operatorname{CONTROLSELECTOR}_{16}(s,&R_1,a_1,d_1,\texttt{*a}_1,j_1,\\ &R_0,a_0,d_0,\texttt{*a}_0,j_0)\\ &=(R,a,d,\texttt{*a},j)=(R_s,a_s,d_s,\texttt{*a}_s,j_s).\end{aligned}\] The values \(R_{1},R_{0}\), and \(R\) are 16-bit; all other arguments and results are bits.