blink.asm

来自「8051试验程序 基础教材」· 汇编 代码 · 共 78 行

;-----------------------------------------------------------------------------
;  Copyright (C) 2005 Silicon Laboratories, Inc.
;  All rights reserved.
;
;
;
;  FILE NAME   :  BLINK.ASM
;  TARGET MCU  :  C8051F040/1/2/3
;  DESCRIPTION :  This program illustrates how to disable the watchdog timer,
;                 configure a port and write to a port I/O pin.
;
; 	NOTES:
;
;-----------------------------------------------------------------------------

#include "ioC8051F040.h"               ; Include register definition file.

;-----------------------------------------------------------------------------
; EQUATES
;-----------------------------------------------------------------------------

GREEN_LED      equ   P1.6              ; Port I/O pin connected to Green LED.	
CONFIG_PAGE    EQU   0FH               ;SYSTEM AND PORT CONFIGURATION PAGE

;-----------------------------------------------------------------------------
; RESET and INTERRUPT VECTORS
;-----------------------------------------------------------------------------

               ; Reset Vector
               ASEGN CSEG01:CODE,0
               ljmp Main               ; Locate a jump to the start of code at
                                       ; the reset vector.

;-----------------------------------------------------------------------------
; CODE SEGMENT
;-----------------------------------------------------------------------------

                RSEG BLINK:CODE  ; code segment

Main:          ; Disable the WDT. (IRQs not enabled at this point.)
               ; If interrupts were enabled, we would need to explicitly disable
               ; them so that the 2nd move to WDTCN occurs no more than four clock
               ; cycles after the first move to WDTCN.

               mov   WDTCN, #0DEh
               mov   WDTCN, #0ADh

               ; Use SFRs on the Configuration Page
               mov   SFRPAGE, #CONFIG_PAGE

               ; Enable the Port I/O Crossbar
               mov   XBR2, #40h

               ; Set P1.6 (LED) as digital output in push-pull mode.
               orl   P1MDOUT,#40h

               ; Initialize LED to OFF
               clr   GREEN_LED

               ; Simple delay loop.
Loop2:         mov   R7, #03h			
Loop1:         mov   R6, #00h
Loop0:         mov   R5, #00h
               djnz  R5, $
               djnz  R6, Loop0
               djnz  R7, Loop1
               cpl   GREEN_LED         ; Toggle LED.
               jmp   Loop2


;-----------------------------------------------------------------------------
; End of file.

              END