startup.as

该程序能够实现四相六线步进电机的正反转功能

	; HI-TECH C PRO for the PIC10/12/16 MCU family V9.60PL5
	; Copyright (C) 1984-2009 HI-TECH Software

	; Auto-generated runtime startup code for final link stage.

	;
	; Compiler options:
	;
	; -omotor.cof -mmotor.map --summary=default --output=default motor.p1 \
	; --chip=16F877A -P --runtime=default --opt=default -D__DEBUG=1 -g \
	; --asmlist --errformat=Error   [%n] %f; %l.%c %s \
	; --msgformat=Advisory[%n] %s --warnformat=Warning [%n] %f; %l.%c %s
	;


	processor	16F877A

	global	_main,start,_exit,reset_vec
	fnroot	_main
	psect	config,class=CONFIG,delta=2
	psect	idloc,class=IDLOC,delta=2
	psect	rbss_0,class=BANK0,space=1
	psect	rbss_1,class=BANK1,space=1
	psect	rbss_2,class=BANK2,space=1
	psect	rbss_3,class=BANK3,space=1
	psect	rdata_0,class=BANK0,space=1
	psect	rdata_1,class=BANK1,space=1
	psect	rdata_2,class=BANK2,space=1
	psect	rdata_3,class=BANK3,space=1
	psect	nvram,class=BANK0,space=1
	psect	nvram_1,class=BANK1,space=1
	psect	nvram_2,class=BANK2,space=1
	psect	nvram_3,class=BANK3,space=1
	psect	nvbit_0,class=BANK0,bit,space=1
	psect	nvbit_1,class=BANK1,bit,space=1
	psect	nvbit_2,class=BANK2,bit,space=1
	psect	nvbit_3,class=BANK3,bit,space=1
	psect	temp,ovrld,class=BANK0,space=1
	psect	struct,ovrld,class=BANK0,space=1
	psect	code,class=CODE,delta=2
	psect	rbit_0,class=BANK0,bit,space=1
	psect	ptbit_0,class=BANK0,bit,space=1
	psect	rbit_1,class=BANK1,bit,space=1
	psect	rbit_2,class=BANK2,bit,space=1
	psect	rbit_3,class=BANK3,bit,space=1
	psect	pstrings,class=CODE,delta=2
	psect	powerup,class=CODE,delta=2
	psect	reset_vec,class=CODE,delta=2
	psect	maintext,class=CODE,delta=2
	C	set	0
	Z	set	2
	PCL	set	2
	INDF	set	0

	psect	fnautoc,class=COMMON,space=1
	psect	common,class=COMMON,space=1
	psect	fnauto0,class=BANK0,space=1
	psect	fnauto1,class=BANK1,space=1
	psect	fnauto2,class=BANK2,space=1
	psect	fnauto3,class=BANK3,space=1
	STATUS	equ	3
	PCLATH	equ	0Ah

	psect	eeprom_data,class=EEDATA,delta=2,space=2
	psect	idata,class=CODE,delta=2
	psect	idata_0,class=CODE,delta=2
	psect	idata_1,class=CODE,delta=2
	psect	idata_2,class=CODE,delta=2
	psect	idata_3,class=CODE,delta=2
	psect	intcode,class=CODE,delta=2
	psect	intret,class=CODE,delta=2
	psect	intentry,class=CODE,delta=2
	global	intlevel0,intlevel1,intlevel2, intlevel3, intlevel4, intlevel5
intlevel0:
intlevel1:
intlevel2:
intlevel3:
intlevel4:
intlevel5:
	psect	intsave,class=BANK0,space=1
	psect	intsave_1,class=BANK1,space=1
	psect	intsave_2,class=BANK2,space=1
	psect	intsave_3,class=BANK3,space=1
	psect	init,class=CODE,delta=2
	psect	init23,class=CODE,delta=2
	psect	text,class=CODE,delta=2
	psect	end_init,class=CODE,delta=2
	psect	clrtext,class=CODE,delta=2
	psect	float_text0,class=CODE,delta=2,size=2048
	psect	float_text1,class=CODE,delta=2,size=2048
	psect	float_text2,class=CODE,delta=2,size=2048
	psect	float_text3,class=CODE,delta=2,size=2048
	psect	float_text4,class=CODE,delta=2,size=2048
	FSR	set	4
	psect	strings,class=CODE,delta=2,reloc=256

	psect	reset_vec
reset_vec:
	; No powerup routine
	global start

; jump to start
	movlw	start >>8
	movwf	PCLATH
	goto	start & 0x7FF | (reset_vec & not 0x7FF)



	psect	init
start
_exit

;-------------------------------------------------------------------------------
;		Clear (zero) uninitialized global variables

;	4 bytes of RAM objects in bank 0 to zero

	psect	init
	global	__Lrbss_0
	movlw	low(__Lrbss_0)		;load the low address into FSR
	movwf	FSR
	movlw	low(__Lrbss_0+4)		;load the high address+1 into W
	fcall	clear_ram		;go and zero that range of addresses

	psect	clrtext,class=CODE,delta=2
	global	clear_ram
;	Called with FSR containing the base address, and
;	W with the last address+1
clear_ram:
	clrwdt			;clear the watchdog before getting into this loop
clrloop:
	clrf	INDF		;clear RAM location pointed to by FSR
	incf	FSR,f		;increment pointer to next location
	xorwf	FSR,w		;XOR with final address
	btfsc	STATUS,2	;have we reached the end yet?
	retlw	0		;all done for this bank, return
	xorwf	FSR,w		;XOR again to restore value
	goto	clrloop		;go and do the next byte

;	No RAM objects to clear in bank 1
;	No RAM objects to clear in bank 2
;	No RAM objects to clear in bank 3
;	6 bytes of RAM objects in common bank to zero

	psect	init
	bsf	STATUS,7		;select indirect bank 2/3
	global	__Lcommon
	movlw	low(__Lcommon)		;load the low address into FSR
	movwf	FSR
	movlw	low(__Lcommon+6)		;load the high address+1 into W
	fcall	clear_ram		;go and zero that range of addresses


;-------------------------------------------------------------------------------
	psect	end_init
	clrf	STATUS
	ljmp _main
	end	start