main.asm

STM8S实验 ASM源程序

stm8/

	#include "mapping.inc"
  #include "STM8S105C_S.inc"

;/******************** stm8单片机实验 ********************
;文件名	: 修改时钟源


;描述   : 修改stm8的时钟源为外部时钟 ，观察LD1灯的变化情况
;*********************************************************

;***************************接线**************************
;硬件：1、STM8s-discovery LED1
 .FORM 72	
lab  equ 2
lab1 equ 3
	
	segment  word 'rom' 
main.l
	; initialize SP
	
 ld a,#{lab mult lab1} 
 %OUT hello!
 ldw X,#stack_end
	ldw SP,X

	#ifdef RAM0	
	; clear RAM0
ram0_start.b EQU $ram0_segment_start
ram0_end.b EQU $ram0_segment_end
	ldw X,#ram0_start
clear_ram0.l
	clr (X)
	incw X
	cpw X,#ram0_end	
	jrule clear_ram0
	#endif

	#ifdef RAM1
	; clear RAM1
ram1_start.w EQU $ram1_segment_start
ram1_end.w EQU $ram1_segment_end	
	ldw X,#ram1_start
clear_ram1.l
	clr (X)
	incw X
	cpw X,#ram1_end	
	jrule clear_ram1
	#endif

	; clear stack
stack_start.w EQU $stack_segment_start
stack_end.w EQU $stack_segment_end
	ldw X,#stack_start
clear_stack.l
	clr (X)
	incw X
	cpw X,#stack_end	
	jrule clear_stack
  
	
 intel
;系统复位后，时钟为内部RC振荡器，16Mhz,8分频，实为2Mhz.
;LD1闪烁10次
  ld a,#10 ;10次	
	bset PD_DDR,#0
	bset PD_CR1,#0
	bres PD_CR2,#0
	
next1
	bres PD_ODR,#0
	call delay
	bset PD_ODR,#0
	call delay
	dec  a
	jrne next1
	
;修改时钟为外部16Mhz时钟.
;LD1闪烁10次

			  mov      CLK_ECKR,#01h       ; 允许外部高速振荡器工作
wait_hse_ready
        ld      a,CLK_ECKR
        and     a,#02h
        jreq    wait_hse_ready       ; 等待外部高速振荡器准备好
				bset    CLK_CSSR,#0        ;CSEEN<-1,时钟安全系统使能
        mov     CLK_SWCR,#02h        ; SWEN <- 1
        mov     CLK_SWR,#0b4h        ; 选择芯片外部的高速振荡器为主时钟
wait_clk_switch
        ld      a,CLK_SWCR
        and     a,#08h
        jreq    wait_clk_switch    ; 等待切换成功

				
next2
	bres PD_ODR,#0
	call delay
	bset PD_ODR,#0
	call delay
	dec  a
	jrne next2				

  jra $ ;

delay
			push cc
			ldw y,#10
loop1	ldw x,#0ffffh
loop	decw x
			jrne loop
			decw y
			jrne loop1
			pop cc
			ret



	interrupt NonHandledInterrupt
NonHandledInterrupt.l
	iret
  
	motorola
	segment 'vectit'
	dc.l {$82000000+main}									; reset
	dc.l {$82000000+NonHandledInterrupt}	; trap
	dc.l {$82000000+NonHandledInterrupt}	; irq0
	dc.l {$82000000+NonHandledInterrupt}	; irq1
	dc.l {$82000000+NonHandledInterrupt}	; irq2
	dc.l {$82000000+NonHandledInterrupt}	; irq3
	dc.l {$82000000+NonHandledInterrupt}	; irq4
	dc.l {$82000000+NonHandledInterrupt}	; irq5
	dc.l {$82000000+NonHandledInterrupt}	; irq6
	dc.l {$82000000+NonHandledInterrupt}	; irq7
	dc.l {$82000000+NonHandledInterrupt}	; irq8
	dc.l {$82000000+NonHandledInterrupt}	; irq9
	dc.l {$82000000+NonHandledInterrupt}	; irq10
	dc.l {$82000000+NonHandledInterrupt}	; irq11
	dc.l {$82000000+NonHandledInterrupt}	; irq12
	dc.l {$82000000+NonHandledInterrupt}	; irq13
	dc.l {$82000000+NonHandledInterrupt}	; irq14
	dc.l {$82000000+NonHandledInterrupt}	; irq15
	dc.l {$82000000+NonHandledInterrupt}	; irq16
	dc.l {$82000000+NonHandledInterrupt}	; irq17
	dc.l {$82000000+NonHandledInterrupt}	; irq18
	dc.l {$82000000+NonHandledInterrupt}	; irq19
	dc.l {$82000000+NonHandledInterrupt}	; irq20
	dc.l {$82000000+NonHandledInterrupt}	; irq21
	dc.l {$82000000+NonHandledInterrupt}	; irq22
	dc.l {$82000000+NonHandledInterrupt}	; irq23
	dc.l {$82000000+NonHandledInterrupt}	; irq24
	dc.l {$82000000+NonHandledInterrupt}	; irq25
	dc.l {$82000000+NonHandledInterrupt}	; irq26
	dc.l {$82000000+NonHandledInterrupt}	; irq27
	dc.l {$82000000+NonHandledInterrupt}	; irq28
	dc.l {$82000000+NonHandledInterrupt}	; irq29

	end