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Example 1: FFT()

include c:\dsp_1for2\dsp_1for2.inc      ;prototypes,  datatypes and structures definitions
includelib c:\dsp_1for2\dsp_1for2.lib      ;import library

N     equ     256

.data?

SignalIn    SIGNAL N dup(?) ;Input signal, array of N points
SpectrumOut COMPLEX N dup(?);Output spectrum, array of N complex points

DspStruct1 DSPSTRUCT <> ;uninitialized DSPSTRUCT structure
.
.

.code
.
.

;The following is in the window procedure:
;----------------------------------------

.if uMsg==WM_CREATE ;initialization

    invoke NewDSP,N,addr dspstruct1,1 ;allocate 1     computation block
;here: fill the input signal (SignalIn) with test values
.
.

.elseif uMsg==WM_COMMAND ;menu
mov eax,wParam ;as any other program

    .if ax==IDM_COMPUTE_SPECTRUM ;user chooses to compute     signal spectrun
        invoke FFT,addr SignalIn,addr           SpectrumOut,DSPSTRUCTs ptr DspStruct1
     ;Note that we passed the 1st 4 members of the DSPSTRUCT structure by casting it to a DSPSTRUCTs structure using "DSPSTRUCTs ptr"
.

.
    .endif ;menu

.elseif uMsg==WM_DESTROY ;clean up

    invoke DeleteDSP,addr dspstruct1

.
.

.endif ;uMsg
 

.
.

end

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