How can I run the pixel shader effect?

Question

Stated below is the code for my pixel shader which I am rendering after the vertex shader. I have set the wordViewProjection matrix in my program but I don't know to set the progress variable i.e in my pixel shader file which will make the image displayed by the help of a quad to give out transition effect. Here is the code for my pixel shader program:::

As my pixel shader is giving a static effect and now I want to use it to give some effect. So for this I have to add a progress variable in my pixel shader and initialize to the Constant table function i.e

constantTable.SetValue(D3DDevice,"progress",progress );

I am having the problem in using this function for progress in my program. Anybody know how to set this variable in my program.

And my new pixel shader code is

float progress : register(C0);
sampler2D implicitInput : register(s0);
sampler2D oldInput : register(s1);

struct VS_OUTPUT
{
    float4 Position  : POSITION;
    float4 Color     : COLOR0;
    float2 UV        : TEXCOORD 0;
};

float4 Blinds(float2 uv)
{               
    if(frac(uv.y * 5) < progress)
    {
        return tex2D(implicitInput, uv);
    }
    else
    {
        return tex2D(oldInput, uv);
    }
}

// Pixel Shader
{
    return Blinds(input.UV);
}