uart.s

360买的双龙M8开发板里CD的程序,正在开发avr板子的学生可以参考一下

	.module uart.c
	.area data(ram, con, rel)
_rd_index::
	.blkb 1
	.area idata
	.byte 0
	.area data(ram, con, rel)
	.dbfile E:\icc\iccavr\mega8\mega8\I2C_COM\uart.c
	.dbsym e rd_index _rd_index c
_wr_index::
	.blkb 1
	.area idata
	.byte 0
	.area data(ram, con, rel)
	.dbfile E:\icc\iccavr\mega8\mega8\I2C_COM\uart.c
	.dbsym e wr_index _wr_index c
	.area vector(rom, abs)
	.org 22
	rjmp _uart_rxc
	.area data(ram, con, rel)
	.dbfile E:\icc\iccavr\mega8\mega8\I2C_COM\uart.c
	.area text(rom, con, rel)
	.dbfile E:\icc\iccavr\mega8\mega8\I2C_COM\uart.c
	.dbfunc e uart_rxc _uart_rxc fV
	.even
_uart_rxc::
	st -y,R2
	st -y,R24
	st -y,R25
	st -y,R30
	st -y,R31
	in R2,0x3f
	st -y,R2
	.dbline -1
	.dbline 19
; /******************************************/
; /*           广州天河双龙电子公司         */
; /*           http://www.sl.com.cn         */
; /*        RS232通信驱动程序(中断方式)     */ 
; /*            作者:[e-mail]         */
; /*               2003年3月28日            */
; /*  目标MCU:MEGA8   晶振:外部(EXT) 8MHZ   */
; /******************************************/
; #include <iom8v.h>
; #include "Twi.h"
; #define fosc 8000000 //晶振8MHZ
; #define baud 19200	 //波特率
; #define buffsize 64
; unsigned char buff[buffsize];
; unsigned char rd_index=0;
; unsigned char wr_index=0;
; #pragma interrupt_handler uart_rxc:iv_USART_RXC
; void uart_rxc(void)
; {
	.dbline 20
;  buff[wr_index]=UDR;
	ldi R24,<_buff
	ldi R25,>_buff
	lds R30,_wr_index
	clr R31
	add R30,R24
	adc R31,R25
	in R2,0xc
	std z+0,R2
	.dbline 21
;  if(wr_index<(buffsize-1))
	lds R24,_wr_index
	cpi R24,63
	brsh L2
	.dbline 22
;     wr_index++;
	subi R24,255    ; addi 1
	sts _wr_index,R24
	rjmp L3
L2:
	.dbline 24
;  else
;     wr_index=0; 
	clr R2
	sts _wr_index,R2
L3:
	.dbline 25
;  TWI_STATE=TWI_WR;//接收数据进入主机传输状态			
	ldi R24,240
	sts _TWI_STATE,R24
	.dbline -2
	.dbline 26
; }
L1:
	ld R2,y+
	out 0x3f,R2
	ld R31,y+
	ld R30,y+
	ld R25,y+
	ld R24,y+
	ld R2,y+
	.dbline 0 ; func end
	reti
	.dbend
	.dbfunc e putchar _putchar fV
;              c -> R16
	.even
_putchar::
	.dbline -1
	.dbline 29
; /*  		字符输出函数 		 */
; void putchar(unsigned char c)
; 	{	 
L5:
	.dbline 30
L6:
	.dbline 30
;      while (!(UCSRA&(1<<UDRE)));
	sbis 0xb,5
	rjmp L5
	.dbline 31
; 	 UDR=c;    
	out 0xc,R16
	.dbline -2
	.dbline 32
; 	}
L4:
	.dbline 0 ; func end
	ret
	.dbsym r c 16 c
	.dbend
	.dbfunc e getchar _getchar fc
;           temp -> R16
	.even
_getchar::
	.dbline -1
	.dbline 35
; /*  		字符输入函数 		 */	
; unsigned char getchar(void)
;  {
	.dbline 37
; 	 unsigned char temp;
; 	 if(wr_index==rd_index)
	lds R2,_rd_index
	lds R3,_wr_index
	cp R3,R2
	brne L9
	.dbline 38
; 	    temp=0;
	clr R16
	rjmp L10
L9:
	.dbline 40
; 	 else
; 	   {
	.dbline 41
; 	    temp=buff[rd_index];
	ldi R24,<_buff
	ldi R25,>_buff
	lds R30,_rd_index
	clr R31
	add R30,R24
	adc R31,R25
	ldd R16,z+0
	.dbline 42
; 		if(rd_index<(buffsize-1))
	lds R24,_rd_index
	cpi R24,63
	brsh L11
	.dbline 43
;     	   rd_index++;
	subi R24,255    ; addi 1
	sts _rd_index,R24
	rjmp L12
L11:
	.dbline 45
;         else
;            rd_index=0; 	
	clr R2
	sts _rd_index,R2
L12:
	.dbline 46
; 	   }  
L10:
	.dbline 47
; 	return temp;   
	.dbline -2
L8:
	.dbline 0 ; func end
	ret
	.dbsym r temp 16 c
	.dbend
	.dbfunc e puts _puts fV
;              s -> R20,R21
	.even
_puts::
	rcall push_gset1
	movw R20,R16
	.dbline -1
	.dbline 51
;  }		
; /*			字符串输出函数	   	 */	
; void puts(char *s)
; 	{
	rjmp L15
L14:
	.dbline 53
	.dbline 54
	movw R30,R20
	ldd R16,z+0
	rcall _putchar
	.dbline 55
	subi R20,255  ; offset = 1
	sbci R21,255
	.dbline 56
L15:
	.dbline 52
; 	while (*s)
	movw R30,R20
	ldd R2,z+0
	tst R2
	brne L14
	.dbline 57
; 		{
; 		putchar(*s);
; 		s++;
; 		}	
;     putchar(0x0a);//回车换行
	ldi R16,10
	rcall _putchar
	.dbline 58
; 	putchar(0x0d);
	ldi R16,13
	rcall _putchar
	.dbline -2
	.dbline 59
; 	}
L13:
	rcall pop_gset1
	.dbline 0 ; func end
	ret
	.dbsym r s 20 pc
	.dbend
	.dbfunc e uart_init _uart_init fV
	.even
_uart_init::
	.dbline -1
	.dbline 62
; /*			UART初始化				*/	
; void uart_init(void)
; {
	.dbline 64
;  //OSCCAL=read_flash(0x1f20);
;  UCSRB=(1<<RXEN)|(1<<TXEN)|(1<<RXCIE);//允许发送、接收及接收中断
	ldi R24,152
	out 0xa,R24
	.dbline 65
;  UBRRL=(fosc/16/(baud+1))%256;
	ldi R24,26
	out 0x9,R24
	.dbline 66
;  UBRRH=(fosc/16/(baud+1))/256;
	clr R2
	out 0x20,R2
	.dbline 67
;  UCSRC=(1<<URSEL)|(1<<UCSZ1)|(1<<UCSZ0);//8位数据+1位STOP位
	ldi R24,134
	out 0x20,R24
	.dbline -2
	.dbline 68
; }
L17:
	.dbline 0 ; func end
	ret
	.dbend
	.area bss(ram, con, rel)
	.dbfile E:\icc\iccavr\mega8\mega8\I2C_COM\uart.c
_buff::
	.blkb 64
	.dbsym e buff _buff A[64:64]c