SUBout O SUBin Gat Ga Cin Full Addar Ful Adder Eul Adar АВ Cin А B Cin АВ Cin АB Cin Full Adder Full Adder Full Adder Full Adder Cout SUM Cout SUM Cout SUM Cout SUM Cout АЗ S3 O B3 A2 S2 O B2 A1 S1 O...

Use any digital logic simulator

Fill-in the blank boxes with the correct LOGIC GATE/ Full/Half Adder

Extracted text: SUBout O SUBin Gat Ga Cin Full Addar Ful Adder Eul Adar АВ Cin А B Cin АВ Cin АB Cin Full Adder Full Adder Full Adder Full Adder Cout SUM Cout SUM Cout SUM Cout SUM Cout АЗ S3 O B3 A2 S2 O B2 A1 S1 O B1 OAO OS


Extracted text: Now, we will modify the subtractor circuit so it can behave as an adder or Your circuit should look something like this: a subtractor depending on the control signal SUB. 1. Open the the 4-bit adder/subtractor circuit (RCAS4.dig) Notice that the only difference from the previous subtractor circuit is the addition of a control signal SUBin, which will tell the circuit whether SUBout SUBIN to add (SUBIN = 0) or subtract (SUBIN = 1). o There is an output pin called SUBout that is simply connected to SUBin. This is just a "convenience port" that provides a wire from the incoming SUB signal to an outgoing SUB signal so you can Cin chain modules together, as you will see later AB Cin B Cin В Cin АВ Cin 2. Now, instead of using a gate which always invert, use a gate that you can use to control when to invert or not, i.e. the one you Full Adder Full Adder Full Adder Full Adder answered in the previous question. Use one such gate for each bit Cout SUM Cout SUM Cout SUM Cout SUM of the operand B before wiring it to the full adder. Each gate should have two inputs: one input line is for a bit of B and the other is the Cout control signal SUB that lets us control whether to invert (during subtraction) or not (during addition). Test if the 4-bit adder/subtractor works as a proper subtractor when SUB=1 and as a proper adder when SUB = 0. Don't forget to properly set Cin when you are subtracting versus when you are adding! O A3 S3 HO B3 HO B2 O A1 S1 O B1 O AO О во OS