initial.asm

有限冲击响应滤波器

	.mmregs
	.global _initial
	.global	_READAD7822
	.global	_WRITEDAC08
	.text 

_initial:
	NOP
	STM #0, CLKMD ; software setting of DSP clock
	STM #0, CLKMD ; (to divider mode before setting)
statu:
    ldm  clkmd, A
	and  #01b, A  ;poll STATUS bit
	bc   statu, ANEQ
	nop
	STM #0x97ff, CLKMD ; set C5402 DSP clock to 100MHz
	rpt  #0ffh
	nop
	nop
	nop
	ld   #0h,dp
	stm  3fa0h,pmst
	stm  7fffh,swwsr	
	nop
	andm    #0fffbh,pmst
	stm		3000h, ar2 	
    nop
	stm   3200h,ar4
	stm   00h,ar3
	ssbx  intm        ;set st1.intm=1 stop all interrupt
	stm   00h,imr     ;stop all interrupt
	stm   0ffffh,ifr  ;clear all interrupt sign
	stm   01h,imr     ;allow int0 interrupt
    nop
	nop
	;andm    #0fffbh,pmst
	nop
	nop
	ret
	
_READAD7822:

   	nop
	andm    #0fffbh,pmst
	stm		3000h,ar1  
	nop
loop0:

	bc loop0,nbio
 	portr 800ch,*ar1
 	andm  #00ffh,*ar1
	ret
    nop
    nop
_WRITEDAC08:
	nop
	stm   3200h,ar4
	nop
	nop	
loop2:	
    bc loop2,  nbio
	portw *ar4,800bh
	ret
	nop
	.end