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器件型号：MSP430F5529 大家好、
#include <msp430.h>
#include <stdint.h>
#include<stdio.h>
#include<math.h>
#define PI 3.1415926535897932384626433832795028841971 //Defines the circumferential rate value
#define FFT_N 128 //Defines the number of points for the benefit leaf transformation
struct compx {float real,imag;}; //Define a complex structure
struct compx s[FFT_N]; //Ft input and output: Start with S[1] and customize by size
int i=0;
float adcresult;
unsigned int *point_1=NULL;
unsigned int DMA_DST[16]; // ADC conversion result is stored in this variable
void adcdma()
{
P1OUT &= ~BIT0; // P1.0 clear
P1DIR |= BIT0; // P1.0 output
P5SEL |= BIT7; // P5.7/TB1 option select
P5DIR |= BIT7; // Output direction
P6SEL |= BIT0; // Enable A/D channel A0
//Setup Timer B0
TBCCR0 = 0xFFFE;
TBCCR1 = 0x8000;
TBCCTL1 = OUTMOD_3; // CCR1 set/reset mode
TBCTL = TBSSEL_2+MC_1+TBCLR; // SMCLK, Up-Mode
// Setup ADC12
ADC12CTL0 = ADC12SHT0_0+ADC12MSC+ADC12ON;// Sampling time, MSC, ADC12 on
ADC12CTL1 = ADC12SHS_3+ADC12CONSEQ_2; // Use sampling timer; ADC12MEM0
// Sample-and-hold source = CCI0B =
// TBCCR1 output
// Repeated-single-channel
ADC12MCTL0 = ADC12SREF_0+ADC12INCH_0; // V+=AVcc V-=AVss, A0 channel
ADC12CTL0 |= ADC12ENC;
// Setup DMA0
DMACTL0 = DMA0TSEL_24; // ADC12IFGx triggered
DMACTL4 = DMARMWDIS; // Read-modify-write disable
DMA0CTL &= ~DMAIFG;
DMA0CTL = DMADT_4+DMAEN+DMADSTINCR_3+DMAIE; // Rpt single tranfer, unchanged dst, Int
DMA0SZ = 16; // DMA0 size = 16
__data20_write_long((uintptr_t) &DMA0SA,(uintptr_t) &ADC12MEM0);
// Source block address
__data20_write_long((uintptr_t) &DMA0DA,(uintptr_t) &DMA_DST);
}
/*******************************************************************
Function prototype：struct compx EE(struct compx b1,struct compx b2)
Function function ：Multiply two complex numbers
Input parameters: Two complex numbers a,b defined in a combination
Output parameters: The product of a and b, which is output in a combination
*******************************************************************/
struct compx EE(struct compx a,struct compx b)
{
struct compx c;
c.real=a.real*b.real-a.imag*b.imag;
c.imag=a.real*b.imag+a.imag*b.real;
return(c);
}
/*****************************************************************
Function prototype ：void FFT(struct compx *xin,int N)
Function function function: Fast Fourier transform on the entered complex array （FFT）
Input Parameters: * the first address pointer of the complex xin structure, struct type
*****************************************************************/
void FFT(struct compx *xin)
{
int f,m,nv2,nm1,i,k,l,j=0;
struct compx u,w,t;
nv2=FFT_N/2; //The variable address operation, which turns the natural order into the reverse order, uses the red algorithm
nm1=FFT_N-1;
for(i=0;i<nm1;i++)
{
if(i<j) //If i<j, the address is changed
{
t=xin[j];
xin[j]=xin[i];
xin[i]=t;
}
k=nv2; //The next reverse order of j is required
while(k<=j) //If k<=j, the highest bit of j is 1
{
j=j-k; //Change the highest bit to 0
k=k/2; //K/2, compare the next high, and so on, compare one by one until a bit is 0
}
j=j+k; //Changed 0 to 1
}
{
int le,lei,ip; //FFT core, which uses a butterfly operation to complete the FFT operation
f=FFT_N;
for(l=1;(f=f/2)!=1;l++) //Computes the value of l, which is the number of butterfly stages
;
for(m=1;m<=l;m++) //Control the number of butterfly junction stages
{ //M represents the class m butterfly, l is the total number of butterfly stages l=log(2)N.
le=2<<(m-1); //Le butterfly junction distance, the butterfly junction of the class m butterfly phase from the le point
lei=le/2; //The distance of two points in the same butterfly junction
u.real=1.0; //U is the butterfly node operating coefficient, with an initial value of 1
u.imag=0.0;
w.real=cos(PI/lei); //W is the coefficient quotient, which is the current coefficients versus the previous coefficients
w.imag=-sin(PI/lei);
for(j=0;j<=lei-1;j++) //The control calculates different types of butterfly knots, which are butterfly knots with different coefficients
{
for(i=j;i<=FFT_N-1;i=i+le) //Control the same butterfly junction operation, which is the same butterfly junction with the same coefficient
{
ip=i+lei; //I, ip represents the two nodes participating in the butterfly operation
t=EE(xin[ip],u); //Butterfly operation, see the equation for details
xin[ip].real=xin[i].real-t.real;
xin[ip].imag=xin[i].imag-t.imag;
xin[i].real=xin[i].real+t.real;
xin[i].imag=xin[i].imag+t.imag;
}
u=EE(u,w); //To change the coefficients for the next butterfly operation
}
}
}
}
int main(void)
{
WDTCTL = WDTPW+WDTHOLD; // Hold WDT
adcdma();
while(!ADC12BUSY==1);
point_1=&DMA_DST;
adcresult=*point_1/1638.4;
for(i=0;i<FFT_N;i++) //Assign values to the structure
{
//adcresult=DMA_DST/1638.4;
//s[i].real=adcresult;
s[i].imag=0; //The imaginary part is 0
}
FFT(s); //For fast benefit leaf changes
for(i=0;i<FFT_N;i++) { //The modulus value of the result after the change is stored in the real part of the complex number
s[i].real=sqrt(s[i].real*s[i].real+s[i].imag*s[i].imag);
}
// Destination single address
__bis_SR_register(LPM0_bits + GIE); // LPM0 w/ interrupts
__no_operation(); // used for debugging
}
//------------------------------------------------------------------------------
// DMA Interrupt Service Routine
//------------------------------------------------------------------------------
#if defined(__TI_COMPILER_VERSION__) || defined(__IAR_SYSTEMS_ICC__)
#pragma vector=DMA_VECTOR
__interrupt void DMA_ISR(void)
#elif defined(__GNUC__)
void __attribute__ ((interrupt(DMA_VECTOR))) DMA_ISR (void)
#else
#error Compiler not supported!
#endif
{
switch(__even_in_range(DMAIV,16))
{
case 0: break;
case 2: // DMA0IFG = DMA Channel 0
P1OUT ^= BIT0; // Toggle P1.0 - PLACE BREAKPOINT HERE AND CHECK DMA_DST VARIABLE
break;
case 4: break; // DMA1IFG = DMA Channel 1
case 6: break; // DMA2IFG = DMA Channel 2
case 8: break; // DMA3IFG = DMA Channel 3
case 10: break; // DMA4IFG = DMA Channel 4
case 12: break; // DMA5IFG = DMA Channel 5
case 14: break; // DMA6IFG = DMA Channel 6
case 16: break; // DMA7IFG = DMA Channel 7
default: break;
}
}
问题：现在无法推导出 DMA 的值、无法将其分配给变量。
您可以帮助检查此案例吗？ 谢谢！
此致、
樱桃
