A typical digital computer has many registers, and paths must be provided to transfer information from one register to another. The number of wires will be excessive if separate lines are used between each register and all other registers in the system. A more efficient scheme for transferring information between registers in a multiple$-$register configuration is a common bus system. A bus structure consists of a set of common lines, one for each bit of a register, through which binary information is transferred one at a time. Control signals deternmine which register is selected by the bus during each particular register transfer.

a$)$ Illustrate System bus system with three$-$state buffers. $($Understand$)(3)$

b$)$ Consider the bus system for four registers using multiplexers and each register has four bits, numbered O through $3.($Apply$)(3)$

c$)$ Which scheme in the above bus system be able to transfer information from any register to any other register? Implement the connections that must be included to provide a path from the outputs of any one register to the Inputs of other register. $($Analyze$)(4)$