sinwaveasm.asm

此程序为TMS320c5410下用汇编语言实现产生一个正弦波

 .title "sin wave..."
 .mmregs
 .global _c_int00,_timer
 .bss buf,128
 .bss con_buf,1
 .bss y0,1 
 .bss y2,1
 .bss y1,1
stack_size .set 0x100
stack .usect ".mstack",stack_size
y12 .word 079bch 
y11 .word 04b3ch 
aa .set  0678eh
bb .set  0c000h
 .text
_c_int00:
 ssbx intm ;关闭所有中断
 ssbx frct ;进行小数运算
 stm #stack+stack_size,sp
 ld #con_buf,dp ;加载dp的值
 stm #0,imr  ;屏蔽所有中断
 stm #0x2020,pmst ;加载pmst的值，其中iptr=0
                  ; 40h,即中断向量指针2000h
 stm #0x0010,tcr ;stop timer0
 stm #2499h,prd   ;store the div
 stm #0x0008,imr  ;turn on the interrupt of timer0
 mvpd y12,y2
 mvpd y11,y1
 stm #buf,ar3
 stm #128,bk
 stm #0x0030,tcr  ;set TRB to load PRD to TIM and PSC to TDDR 
 ;nop
 stm #0x0000,tcr  ;start timer0
 rsbx intm        ;turn on all interrupt

again:
	b again

_timer:
 pshm st0
 pshm st1

 mpy y1,#bb,a
 ltd y2
 mac #aa,a
 sth a,1,y2
 ld #buf,dp
 sth a,1,*ar3+%
 nop
 nop
 popm st1
 popm st0
 rete