基于VB 的频谱分析仪些许问题

我想请问：
基于VB 的频谱分析仪
需要实现的是从串口实现数据的采集，后存入数组中，然后进行FFT 的变化，把变换的图形在界面上显示出来，结果图形必须在有坐标轴的界面上。
这个是一个FFT的模块程序。现在需要自己定义一个函数，存入数组中（类似于方波（0，0，0，1，1，1，0，0，0）），来检验FFT模块是否正确。该如何下手。
Private Sub CommandFFT_Click()

N=256
R=8
Dim TR (0 To 256) As Single, TI (0 To 256) As Single,R2 (0 To 256) As Single
Dim TR1, A As Single, K,Q,L As Integer
Dim TI1, A1,A2 As Single
For K= 0 To N
   TR(K) = e (K)
   TI(K) = 0
     'Print "    "; TR(K),TI(K)
     Next K
85   For L = 1 To R
     N1= 2^(R-L)
     P = 0
540  G = P
    GoSub 1000
    A = 2*3.1415926*D/N
    A1 = Cos(A)
    A2 = Sin(A)
    For K = P* N1 To (P+1) *N1 -1
    TR1 = TR(K+N1) *A1 +TI(K+N1) *A2
    TI1 = TI(K+N1) *A1 - TR(K+N1) *A2
    TR(K+N1) = TR(K) - TR1
    TI(K+N1) = TI(K) - TI1
    TR(K) = TR(K) +TR1
    TI(K) = TI(K) +TI1
    Next K
    P = P+2
    If (P+1) * N1 < N Then Go To 540
    Next L
    For K = 0 To N-1
    G = K
    GoSub 1000
     If K >= D Then Go To 800
    TR1 = TR(K)
    TI1 = TI(K)
    TR(K) =TR(D)
    TI(K) =TI(D)
    TR(D) = TR1
    TI(D) = TI1
800  Next K
    Cls
    Scale (0,64)-(128,-64)
     DrawWidth = 1
     Line (0,0)-(128,0), RGB(0,0,255)
     Line (0,64)-(0,-64), RGB(0,0,255)
     For K =0 To N-1
      R2(K) = Sqr(TR(K) * TR(K) + TI(K)* TI(K))
820  'Print K; Tab(8); TR(K);Tab(24);TI(K);Tab(50);R2(K)
     DrawWidth = 1
      PSet (K,R2(K)), RGB(255,0,0)
      Line (K,R2(K))-(K,0), RGB(255,0,255)
      Next K
      Go To 86
1000  D = 0
      For Q = 1 To R
      C = Int(G / 2)
      D = 2*D+G-2* C
      G = C
      Next Q
      Return\
86    End Sub

  请高手专家帮帮忙啊 ·· --------------------编程问答--------------------

补充：VB ,  网络编程

基于VB 的频谱分析仪 些许问题

基于VB 的频谱分析仪些许问题