uart_test.s

avr单片机的串口程序

	.module uart_test.c
	.area text(rom, con, rel)
	.dbfile F:\avrprojs\uart_test\uart_test.c
	.dbfunc e delay _delay fV
;              i -> y+0
	.even
_delay::
	rcall push_gset2
	sbiw R28,4
	.dbline -1
	.dbline 4
; #include <iom48v.h>
; 
; void delay(void)
; {
	.dbline 6
	ldi R20,0
	ldi R21,0
	ldi R22,0
	ldi R23,0
	movw R30,R28
	std z+0,R20
	std z+1,R21
	std z+2,R22
	std z+3,R23
	rjmp L5
L2:
	.dbline 6
L3:
	.dbline 6
	ldi R20,1
	ldi R21,0
	ldi R22,0
	ldi R23,0
	movw R30,R28
	ldd R2,z+0
	ldd R3,z+1
	ldd R4,z+2
	ldd R5,z+3
	add R2,R20
	adc R3,R21
	adc R4,R22
	adc R5,R23
	movw R30,R28
	std z+0,R2
	std z+1,R3
	std z+2,R4
	std z+3,R5
L5:
	.dbline 6
;   unsigned long i;
;   for(i=0;i<11142;i++);
	ldi R20,134
	ldi R21,43
	ldi R22,0
	ldi R23,0
	movw R30,R28
	ldd R2,z+0
	ldd R3,z+1
	ldd R4,z+2
	ldd R5,z+3
	cp R2,R20
	cpc R3,R21
	cpc R4,R22
	cpc R5,R23
	brlo L2
	.dbline -2
L1:
	adiw R28,4
	rcall pop_gset2
	.dbline 0 ; func end
	ret
	.dbsym l i 0 l
	.dbend
	.dbfunc e uart0_init _uart0_init fV
	.even
_uart0_init::
	.dbline -1
	.dbline 10
; }
; 
; void uart0_init(void)
; {
	.dbline 12
; 
;  UCSR0B = 0x00; //disable while setting baud rate
	clr R2
	sts 193,R2
	.dbline 13
;  UCSR0A = 0x00;
	sts 192,R2
	.dbline 14
;  UCSR0C = 0x0E;
	ldi R24,14
	sts 194,R24
	.dbline 15
;  UBRR0L = 0x6; //set baud rate lo
	ldi R24,6
	sts 196,R24
	.dbline 16
;  UBRR0H = 0x00; //set baud rate hi
	sts 197,R2
	.dbline 17
;  UCSR0B = 0x08;
	ldi R24,8
	sts 193,R24
	.dbline -2
L6:
	.dbline 0 ; func end
	ret
	.dbend
	.dbfunc e sendchar _sendchar fV
;              c -> R16
	.even
_sendchar::
	.dbline -1
	.dbline 25
; //  UBRR0 =0x33;
; //  UCSR0B=0x08;
; //  UCSR0C=0x0e;
; //  UBRR0L=0x6;
; }
; 
; void sendchar(unsigned char c)
; {
	.dbline 27
;   // while(!(UCSR0A&0x40));
;       UDR0=c;
	sts 198,R16
L8:
	.dbline 28
L9:
	.dbline 28
; 	  while(!(UCSR0A&0x40));
	lds R2,192
	sbrs R2,6
	rjmp L8
	.dbline -2
L7:
	.dbline 0 ; func end
	ret
	.dbsym r c 16 c
	.dbend
	.dbfunc e main _main fI
;              i -> R20,R21
	.even
_main::
	.dbline -1
	.dbline 32
; }
; 
; main()
; {
	.dbline 34
;  int i;
;  uart0_init();
	rcall _uart0_init
	rjmp L13
L12:
	.dbline 36
;  while(1)
;  {
	.dbline 37
;    delay();
	rcall _delay
	.dbline 39
;   
;    sendchar('0'+i);
	mov R16,R20
	subi R16,208  ; offset = 48
	sbci R17,255
	rcall _sendchar
	.dbline 40
;    i=i+1;
	subi R20,255  ; offset = 1
	sbci R21,255
	.dbline 41
;    if(i>=10)
	cpi R20,10
	ldi R30,0
	cpc R21,R30
	brlt L15
	.dbline 42
;    i=0;
	clr R20
	clr R21
L15:
	.dbline 43
L13:
	.dbline 35
	rjmp L12
X0:
	.dbline -2
L11:
	.dbline 0 ; func end
	ret
	.dbsym r i 20 I
	.dbend