//
// Title      : (164) 8-BIT PARALLEL-OUT SERIAL SHIFT REGISTERS
// File name  : 164.v
// Date       : 2000/12/08  Ver1.0
// Company    : Future Technology Ltd.
//

//---------------------------------------------------------
//  Module
//---------------------------------------------------------

module U164 (
            XCLR,
            CLK,
            A,
            B,
            QA,
            QB,
            QC,
            QD,
            QE,
            QF,
            QG,
            QH
        );

    input       XCLR;
    input       CLK;
    input       A;
    input       B;
    output      QA;
    output      QB;
    output      QC;
    output      QD;
    output      QE;
    output      QF;
    output      QG;
    output      QH;

//----------------------------------------------------------
//  Using register
//----------------------------------------------------------
    reg         QA;
    reg         QB;
    reg         QC;
    reg         QD;
    reg         QE;
    reg         QF;
    reg         QG;
    reg         QH;


    always@(negedge XCLR or posedge CLK)begin
        if(XCLR==1'b0)begin
            QA <= 1'b0;
            QB <= 1'b0;
            QC <= 1'b0;
            QD <= 1'b0;
            QE <= 1'b0;
            QF <= 1'b0;
            QG <= 1'b0;
            QH <= 1'b0;
        end else begin
            QA <= A & B;
            QB <= QA;
            QC <= QB;
            QD <= QC;
            QE <= QD;
            QF <= QE;
            QG <= QF;
            QH <= QG;
        end
    end

endmodule