CSE 404 Digital System Design Sessional

12 downloads 956 Views 80KB Size Report
Digital System Design Sessional. Specification for 4 ... 4 bit ALU Design Specification ... Digital Logic and Computer Design – M. Morris Mano (Page – 367-382).
CSE 404 Digital System Design Sessional Specification for 4 bit ALU 4 bit ALU Design Specification A (input)

B (input)

A3 A2 A1 A0

B3 B2 B1 B0

Arithmetic Logic Unit (ALU)

Cout (Output carry)

}Selection Cin

F3 F2 F1 F0

Flags

F (Output)

Block diagram of 4 bit ALU Functions: Function Transfer A Increment A Decrement A Addition Subtraction Addition with carry Subtraction with borrow AND OR XOR Complement A

Output F=A F=A+1 F=A–1 F=A+B F=A–B F=A+B+1 F=A–B–1 F = A.B F=A+B F = A XOR B F=Ā

Required Flags: o Carry o Sign o Overflow o Zero Design and Implementation Issues: o All outputs and flag status must be directed to LED. o Flags will be affected as per the rules of Assembly Language (See Kip. R. Irvine). o Any SSI (AND, OR, NOT, XOR etc.) and MSI (MUX, Decoder, Adder etc.) chip can be used. o Emphasis should be given on efficiency of design and minimization of ICs used. o Late submission will result in reduced marking. Reference: Digital Logic and Computer Design – M. Morris Mano (Page – 367-382)