DSP课程设计---正弦波信号发生器.doc

题目一：正弦波信号发生器一、 设计题目：正弦波信号发生器二、 设计目的： 1、掌握正弦波发生器的工作原理 2、掌握如何用汇编语言实现正弦波信号发生器 3、熟悉ccs操作环境三、设计要求： 1、用汇编语言设计一个正弦波信号发生器 2、在ccs环境下实现正弦信号发生器四、设计原理：正弦波信号发生器已被广泛地应用于通信、仪器仪表和工业控制等领域的信号处理系统中。通常有两种方法可以产生正弦波，分别为查表法和泰勒级数展开法。查表法主要用于精度要求不是很高的场合，而泰勒级数展开法是一种比查表法更为有效的方法，它能精确地计算出一个角度的正弦值和余弦值，且只需较小的存储空间。五、正弦波的实现利用计算一个角度的正弦值和余弦值可实现正弦波。其实现步骤如下：第一步：利用sin_start和cos_start子程序，计算045（间隔为0.5）的正弦值和余弦值；第二部：利用sin(2x)=2sin(x)cos(x)公式，计算090的正弦值（间隔为1）；第三部：通过复制，获得0359的正弦值；第四步：将0359的正弦值重复从pa口输出，便可得到正弦波。产生正弦波源程序清单sin.asm：.title “sin.asm” .mmregs .def start .def d_xs,d_sinx,d_xc,d_cosx,sinx,cosxsin_x: .usect sin_x,360stack: .usect stack,10hk_theta .set 286 ;theta=pi/360(0.5deg)start: .text stm #stack+10h,sp stm k_theta,ar0 stm 0,ar1 stm #sin_x,ar6 stm #90,brc rptb loop1-1 ldm ar1,a ld #d_xs,dp stl a,d_xs stl a,d_xc call sinx ;d_sinx=sin(x) call cosx ;d_cosx=cos(x) ld #d_sinx,dp ld d_sinx,16,a ;a=sin(x) mpya d_cosx ;b=sin(x)*cos(x) sth b,1,*ar6+ ;ar6-2*sin(x) mar *ar1+0loop1: stm #sin_x+89, ar7 ;sin91(deg.)-sin179(deg.) stm #88,brc rptb loop2-1 ld *ar7-,a stl a,*ar6+loop2: stm #179,brc ;sin180(deg.)-sin359(deg.) stm #sin_x,ar7 rptb loop3-1 ld *ar7+,a neg a stl a,*ar6+loop3: stm #sin_x,ar6 ;generate sin wave stm #1,ar0 stm #360,bk b loop3sinx: .def d_xs,d_sinx .datatable_s .word 01c7h ;c1=1/(8*9) .word 030bh ;c2=1/(6*7) .word 0666h ;c3=1/(4*5) .word 1556h ;c4=1/(2*3)d_coef_s .usect coef_s,4d_xs .usect sin_vars,1d_squr_xs .usect sin_vars,1d_temp_s .usect sin_vars,1d_sinx .usect sin_vars,1d_l_s .usect sin_vars,1 .text ssbx frct stm #d_coef_s,ar5 ;move coeffs table_s rpt #3 mvpd #table_s,*ar5+ stm #d_coef_s,ar3 stm #d_xs,ar2 stm #d_l_s,ar4 st #7fffh,d_l_s squr *ar2+,a ;a=x2 st a,*ar2 ;(ar2)=x2 |ld *ar4,b ;b=1 masr *ar2+,*ar3+,b,a ;a=1-x2/72,t=x2 mpya a ;a=t*a=x2(1-x2/72) sth a,*ar2 ;(d_temp)=x2(1-x2/72) masr *ar2-,*ar3+,b,a ;a=1-x2/42(1-x2/72);t=x2(1-x2/72) mpya *ar2+ ;b=x2(1-x2/42(1-x2/72) st b,*ar2 ;(d_temp)=x2(1-x2/42(1-x2/72) |ld *ar4,b ;b=1 masr *ar2-,*ar3+,b,a ;a=1-x2/20(1-x2/42(1-x2/72) mpya *ar2+ ;b=x2(1-x2/20(1-x2/42(1-x2/72) st b,*ar2 ;(d_temp)=b |ld *ar4,b ;b=1 masr *ar2-,*ar3+,b,a ;a=1-x2/6(1-x2/20(1-x2/42(1-x2/72) mpya d_xs ;b=x(1-x2/6(1-x2/20(1-x2/42(1-x2/72) sth b,d_sinx ;sin(theta) retcosx: .def d_xc,d_cosxd_coef_c .usect coef_c,4 .datatable_c .word 0249h ;c1=1/(7*8) .word 0444h ;c2=1/(5*6) .word 0aabh ;c3=1/(3*4) .word 4000h ;c4=1/2d_xc .usect cos_vars,1d_squr_xc .usect cos_vars,1d_temp_c .usect cos_vars,1d_cosx .usect cos_vars,1c_l_c .usect cos_vars,1 .text ssbx frct stm #d_coef_c,ar5 ;move coeffs table_c rpt #3 mvpd #table_c,*ar5+ stm #d_coef_c,ar3 stm #d_xc,ar2 stm #c_l_c,ar4 st #7fffh,c_l_c squr *ar2+,a ;a=x2 st a,*ar2 ;(ar2)=x2 |ld *ar4,b ;b=1 masr *ar2+,*ar3+,b,a ;a=1-x2/56,t=x2 mpya a ;a=t*a=x2（1-x2/56） sth a,*ar2 ;(d_temp)=x2(1-x2/56) masr *ar2-,*ar3+,b,a ;a=1-x2/30(1-x2/56); t=x2(1-x2/56) mpya *ar2+ ;b=x2(1-x2/30(1-x2/56) st b,*ar2 ;(d_temp)=x2(1-x2/30(1-x2/56) |ld *ar4,b ;b=1 masr *ar2-,*ar3+,b,a ;a=1-x2/12(1-x2/30(1-x2/56) sfta a,-1,a ;-1/2 neg a mpya *ar2+ ;b=-x2/2(1-x2/12(1-x2/30(1-x2/56) mar *ar2+ retd add *ar4,16,b ;b=-x2/2(1-x2/12(1-x2/30(1-x2/56) sth b,*ar2 ;cos(theta) ret .end产生正弦波链接命令文件sin.cmd memory page 0: eprom: org=0e000h, len=1000h vecs: org=0ff80h, len=0080h page 1: spram: org=0060h, len=0020h daram1: org=0080h, len=0010h daram2: org=0090h, len=0010h daram3: org=0200h, len=0200h sections .text : eprom page 0 .data : eprom page 0 stack : spram page 1 sin_vars : daram1 page 1 coef_s : dara