Control Unit Working

R1

R2

PC

MDR

MAR

Y

Z

IR

Control/Decode Unite

Constant 4

1

R1

R1

PC

MDR

MAR

Y

IR

Control/Decode Unite

Pcout, MARin, Read, Select4, Add, Zin

Z

Constant 4

R2

2

R1

R1

PC

MDR

MAR

Y

IR

Control/Decode Unite

Pcout, MARin, Read, Select4, Add, Zin

Z

Constant 4

MAR

R2

3

R1

R1

PC

MDR

MAR

Y

IR

Control/Decode Unite

Pcout, MARin, Read, Select4, Add, Zin

Z

Constant 4

MARRead

R2

4

R1

R1

PC

MDR

MAR

Y

IR

Control/Decode Unite

Pcout, MARin, Read, Select4, Add, Zin

Z

Constant 4

MARRead

Select4

R2

5

R1

R1

PC

MDR

MAR

Y

IR

Control/Decode Unite

Pcout, MARin, Read, Select4, Add, Zin

Z

Constant 4

MARRead

Select4

ADDPC+4

R2

6

R1

R1

PC

MDR

MAR

Y

IR

Control/Decode Unite

Pcout, MARin, Read, Select4, Add, Zin

Z

Constant 4

MARRead

Select4

ADDPC+4

Z

R2

7

R1

R1

PC

MDR

MAR

Y

Z

IR

Control/Decode Unite

Constant 4

Zout, Pcin, Yin, WMFC

R2R2

8

R1

R1

PC

MDR

MAR

Y

Z

IR

Control/Decode Unite

Constant 4

Zout, Pcin, Yin, WMFC

PC

R2

9

R1

R1

PC

MDR

MAR

Y

Z

IR

Control/Decode Unite

Constant 4

Zout, Pcin, Yin, WMFC

PC

Y

R2

10

R1

R1

PC

MDR

MAR

Y

Z

IR

Control/Decode Unite

Constant 4

Zout, Pcin, Yin, WMFC

PC

Y

WMFC

Waiting for the Data to come from the memory. When the data or Instruction is available, it will be Latched into MDR

R2

11

R1

R1

PC

MDR

MAR

Y

Z

IR

Control/Decode Unite

Constant 4

MDRout, IRin

PC

Y

R2

12

R1

R2

PC

MDR

MAR

Y

Z

IR

Control/Decode Unite

Constant 4

MDRout, IRin

PC

Y

IR

ADD R1, R2

13

R1

R2

PC

MDR

MAR

Y

Z

IR

Control/Decode Unite

Constant 4

R1out, Yin, SELECTY

PC

Y

IR

ADD R1, R2

14

R1

R2

PC

MDR

MAR

Y

Z

IR

Control/Decode Unite

Constant 4

R1out, Yin, SELECTY

PC

Y

IR

ADD R1, R2

Y

15

R1

R2

PC

MDR

MAR

Y

Z

IR

Control/Decode Unite

Constant 4

R1out, Yin, SELECTY

PC

Y

IR

ADD R1, R2

Y

SelectY

16

R1

R2

PC

MDR

MAR

Y

Z

IR

Control/Decode Unite

Constant 4

R2out, ADD, Zin

PC

Y

IR

ADD R1, R2

Y

SelectY

17

R1

R2

PC

MDR

MAR

Y

Z

IR

Control/Decode Unite

Constant 4

R2out, ADD, Zin

PC

Y

IR

ADD R1, R2

Y

SelectY

ADD

18

R1

R2

PC

MDR

MAR

Y

Z

IR

Control/Decode Unite

Constant 4

R2out, ADD, Zin

PC

Y

IR

ADD R1, R2

Y

SelectY

ADD

Z19

R1

R2

PC

MDR

MAR

Y

Z

IR

Control/Decode Unite

Constant 4

Zout, R1in, END

PC

Y

IR

ADD R1, R2

Y

SelectY

ADD

Z20

R1

R2

PC

MDR

MAR

Y

Z

IR

Control/Decode Unite

Constant 4

Zout, R1in, END

PC

Y

IR

ADD R1, R2

Y

SelectY

ADD

Z

R1

21

R1

R2

PC

MDR

MAR

Y

Z

IR

Control/Decode Unite

Constant 4

Zout, R1in, END

PC

Y

IR

ADD R1, R2

Y

SelectY

ADD

Z

R1

22