National Instruments 320571-01 用户手册

                                                                                                        

 

This chapter contains an overview of the prototypes of the C-callable NI-DSP Analysis functions on the DSP board
that you can use in your custom programs.

Every NI-DSP Analysis VI calls a function on the DSP board.  When you write your own custom functions, you can
call these functions from your program.  These C functions include numerical analysis, signal generation, digital
signal processing, digital filtering, windowing, and memory management.

For more information about these functions, refer to the NI-DSP Software Reference Manual for DOS/LabWindows.

Note:

The functions listed in this chapter are the same functions described in the NI-DSP Software Reference
Manual for DOS/LabWindows, except for the following differences:

•

For all of the functions, ignore the slot number parameter specified in the tables of parameters.  The
slot number is not meaningful when you call these functions from the DSP board.

•

The integer parameters are all 32 bits long.  The corresponding parameter type in the NI-DSP Software
Reference Manual for DOS/LabWindows  is 16-bit integer.  When you call these functions in your
custom program, use the 32-bit long type defined in this manual.  Use the data types defined in this
manual rather than the data types for similar functions listed in any other manual.  The parameter order
and meaning and the purpose of the functions, however, are equivalent with the functions described in
the NI-DSP Software Reference Manual for DOS/LabWindows.

•

The functions listed are all of the functions that you can call from your custom program.  Not all the
functions described in the NI-DSP Software Reference Manual for DOS/LabWindows are available in
NI-DSP for LabVIEW for Windows.

The following is a list of the prototypes of each function that you can customize for use on the DSP board.

Signals

short DSP_Gaussian (long n, float sDev, float* noise, float seed)
short DSP_ImpTrain (long n, float amp, long delay, long period, float * x)
short DSP_Impulse (long n, float amp, long index, float * x)
short DSP_Pulse (long n, float amp, long delay, long width, float *x)
short DSP_Ramp (long n, float  first, float last, float * x)
short DSP_Sawtooth (long n, float amp, long delay, float cycles, float * x)
short DSP_Sinc (long n, float amp, float delay, float dt, float *x)
short DSP_Sine (long n, float amp, float phase, float cycles, float * x)
short DSP_Square (long n, float amp, float duty, float cycles, float * y)
short DSP_Triangle

(long n, float amp, float delay, float width,
float dt, float * x)

short DSP_TriTrain (long n, float amp, long delay, float cycles, float * x)
short DSP_Uniform (long n, float * noise, float seed)
short DSP_WhiteNoise (long n, float amp, float * noise, float seed)

Frequency Domain

short DSP_CrossPower (float * x, float * y, long n)
short DSP_CxFFT (float * x, float * y, long n)
short DSP_FHT (float * x, long n)
short DSP_InvFFT (float * x, float * y, long n)
short DSP_InvFHT (float * x, long n)
short DSP_ReFFT (float * x, float * y, long n)
short DSP_Spectrum (float * x, long n)
short DSP_ZeroPad (float * x, long n, long size)