- 基于TMS320C54x_DSP的函数发生器的设计

  .mmregs
.global main
.def start
.ref d_xs,d_sinx,d_xc,d_cosx,sinx,cosx
sin_x:     .usect "sin_x",360
cos_x:     .usect "cos_x",360
fangbo:  .usect "fangbo",360
STACK:     .usect "STACK",10H
k_theta   .set 286
TIM0 .set 0024H
PRD0 .set 0025H
TCR0 .set 0026H
PA    .set 0100H


.text
start:     
 ;产生正弦波数据
       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
       CALL   cosx
       LD     #d_sinx,DP
       LD     @d_sinx,16,A
       MPYA   @d_cosx
       STH      B,1,*AR6+
       MAR      *AR1+0
loop1: STM     #sin_x+89,AR7
       STM      #88,BRC
       RPTB   loop2-1
       LD     *AR7-,A
       STL      A,*AR6+
loop2:    STM      #179,BRC
       STM      #sin_x,AR7
       RPTB   loop3-1
       LD     *AR7+,A
       NEG      A
       STL      A,*AR6+
loop3:STM    #sin_x+89,AR6
   STM      #cos_x,AR7
         STM      #269,BRC             
         RPTB   lcos-1          
         LD     *AR6+,A
       STL      A,*AR7+
lcos:    STM      #sin_x,AR6
      STM      #89,BRC             
         RPTB   loop4-1          
         LD     *AR6+,A
       STL      A,*AR7+
 
;产生方波数据
 
loop4: STM   #fangbo,AR6
       STM      #179,BRC             
        RPTB    lfangbo-1          
        LD      #7FFFH,A
       STL      A,*AR6+
lfangbo:
STM      #179,BRC             
        RPTB    main-1          
        LD      #0H,A
       STL      A,*AR6+
 
main:  

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