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// lab4b.c // Uses PN generation, IIR filtering, and autocorrelation // code by Matt Kleffner -9/2004 // Based on swi_process.c by Educational DSP #include "dsk5510_dual3006cfg.h" #include "dsk5510.h" #include "swi_process.h" #include "dsplib.h" #include "lab4b.h" /* Define N here in header file */ /* function defined in pn.c */ void rand_fillbuffer(void); /* IIR values and buffers (declared in c_fft_given_iirc.asm) */ #define IIR_order 4 extern int scale; extern int coef[IIR_order]; extern int state[IIR_order]; /* Pointer to state buffer location */ int iirptr; extern unsigned int *iseed; /* seed for rand_fillbuffer() and randbit() */ /* function defined in iirfilt.c */ void iirfilt(void); /* function defined in autocorr.c */ void autocorr(void); /* Function defined by c_fft_given_iirc.asm */ //void bit_rev_fft(void); /* FFT data buffers (declared in c_fft_given_iirc.asm) */ extern int bit_rev_data[N*2]; /* Data output for bit-reverse function */ extern int fft_data[N*2]; /* In-place FFT input & Output array */ /* Our input/output buffers */ int autocorr_in[N]; int autocorr_out[N]; // all data processing should be done in SWI_ProcessBuffer void SWI_ProcessBuffer() { static unsigned int mbox_value = 0; short *psrc, *pdest; unsigned int i; mbox_value |= SWI_getmbox(); // buffers are only processed when both transmit and receive are ready if((mbox_value & DMA_RECEIVE_DONE) && (mbox_value & DMA_TRANSMIT_DONE)) { mbox_value = 0; // get buffer pointers psrc = receive_buffer[receive_buffer_to_process_index]; pdest = transmit_buffer[transmit_buffer_to_fill_index]; /* First, transfer inputs and outputs */ for (i = 0; i < N; i++) { pdest[4*i] = autocorr_in[i]; pdest[4*i+1] = bit_rev_data[i*2] << 8; /* Some statements useful in debugging */ /* pdest[4*i] = psrc[4*i+2]; */ /* Be sure to comment out PN-sequence generation */ /* when using the next two lines */ //autocorr_in[i] = psrc[4i+2]; } /* Last, set the DC coefficient to -1 for a trigger pulse */ pdest[0] = -32768; /* Generate PN input */ rand_fillbuffer(); /* Filter input */ iirfilt(); /* Calculate autocorrelation */ autocorr(); /* Transfer autocorr output to FFT input buffer */ for (i = 0; i < N; i++) { fft_data[i*2] = autocorr_out[i]; fft_data[i*2+1] = 0; } // Bit-reverse and compute FFT cfft((DATA *)fft_data,N, SCALE); cbrev((DATA *)fft_data,(DATA *)bit_rev_data,N); /* Done, wait for next time around! */ receive_buffer_processed = 1; // flag receive buffer as processed transmit_buffer_filled = 1; // flag output buffer as full } } // lab4bmain.c // based on main.c by Educational DSP // Initializes autocorr_out, state, and iseed. // Can be modified for optimization. #include "dsk5510_dual3006cfg.h" #include "dsk5510.h" #include <csl.h> #include "lab4b.h" #define IIR_order 4 extern int iirptr; unsigned int *iseed; extern int autocorr_out[N]; extern int state[IIR_order]; void init_DMA(); void main() { int i; DSK5510_init(); // init BSL DSK5510_rset(DSK5510_MISC, 0x03); // route McBSP0/1 to J3 // Initialize autocorr_out to zero since some values will remain zero for (i = 0; i < N; ++i) { autocorr_out[i] = 0; } for ( i = 0; i < IIR_order; ++i) state[i] = 0; // Start McBSP0 I2S slave MCBSP_start(hMcbsp0, MCBSP_XMIT_START | MCBSP_RCV_START | MCBSP_SRGR_START | MCBSP_SRGR_FRAMESYNC, 220); // Start McBSP1 I2S master MCBSP_start(hMcbsp1, MCBSP_XMIT_START | MCBSP_RCV_START | MCBSP_SRGR_START | MCBSP_SRGR_FRAMESYNC, 220); init_DMA(); // configure DMA and interrupts *iseed = 1; iirptr = 0; return; // let DSP/BIOS scheduler take over }

Questions & Answers

what does nano mean?
Anassong Reply
nano basically means 10^(-9). nanometer is a unit to measure length.
do you think it's worthwhile in the long term to study the effects and possibilities of nanotechnology on viral treatment?
Damian Reply
absolutely yes
how to know photocatalytic properties of tio2 nanoparticles...what to do now
Akash Reply
it is a goid question and i want to know the answer as well
characteristics of micro business
for teaching engĺish at school how nano technology help us
Do somebody tell me a best nano engineering book for beginners?
s. Reply
what is fullerene does it is used to make bukky balls
Devang Reply
are you nano engineer ?
fullerene is a bucky ball aka Carbon 60 molecule. It was name by the architect Fuller. He design the geodesic dome. it resembles a soccer ball.
what is the actual application of fullerenes nowadays?
That is a great question Damian. best way to answer that question is to Google it. there are hundreds of applications for buck minister fullerenes, from medical to aerospace. you can also find plenty of research papers that will give you great detail on the potential applications of fullerenes.
what is the Synthesis, properties,and applications of carbon nano chemistry
Abhijith Reply
Mostly, they use nano carbon for electronics and for materials to be strengthened.
is Bucky paper clear?
so some one know about replacing silicon atom with phosphorous in semiconductors device?
s. Reply
Yeah, it is a pain to say the least. You basically have to heat the substarte up to around 1000 degrees celcius then pass phosphene gas over top of it, which is explosive and toxic by the way, under very low pressure.
Do you know which machine is used to that process?
how to fabricate graphene ink ?
for screen printed electrodes ?
What is lattice structure?
s. Reply
of graphene you mean?
or in general
in general
Graphene has a hexagonal structure
On having this app for quite a bit time, Haven't realised there's a chat room in it.
what is biological synthesis of nanoparticles
Sanket Reply
what's the easiest and fastest way to the synthesize AgNP?
Damian Reply
types of nano material
abeetha Reply
I start with an easy one. carbon nanotubes woven into a long filament like a string
many many of nanotubes
what is the k.e before it land
what is the function of carbon nanotubes?
I'm interested in nanotube
what is nanomaterials​ and their applications of sensors.
Ramkumar Reply
what is nano technology
Sravani Reply
what is system testing?
preparation of nanomaterial
Victor Reply
how to synthesize TiO2 nanoparticles by chemical methods
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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Source:  OpenStax, Digital signal processing laboratory (ece 420 55x). OpenStax CNX. Jan 18, 2010 Download for free at http://cnx.org/content/col10397/1.10
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