serial.s

用avr单片机接收GPS的数据的ｃ语言程序

	.module serial.c
	.area text(rom, con, rel)
	.dbfile E:\Program\gps\serial.c
	.dbfunc e uart0_init _uart0_init fV
	.even
_uart0_init::
	.dbline -1
	.dbline 24
; //ICC-AVR application builder : 2006-5-8 20:10:07
; // Target : M16
; // Crystal: 8Mhz
; 
; #include <iom32v.h>
; #include <macros.h>
; #include <serial.h>
; 
; #define  max 1024
; 
; /* Static Variables */
; int         count;
; char  		rcv_buf[max];
; int         UART_wp;//write data to receive buffer
; int         read_pt;//read pointer: read data from receive buffer
; 
; 
; //UART0 initialize
; // desired baud rate: 4800
; // actual: baud rate:4800 (0.0%)
; // char size: 8 bit
; // parity: Disabled
; void uart0_init(void)
; {
	.dbline 26
; 
;  UCSRB = 0x00; //disable while setting baud rate
	clr R2
	out 0xa,R2
	.dbline 27
;  UCSRA = 0x00;
	out 0xb,R2
	.dbline 28
;  UCSRC = BIT(URSEL) | 0x06;
	ldi R24,134
	out 0x20,R24
	.dbline 29
;  UBRRL = 0XCF; //set baud rate lo
	ldi R24,207
	out 0x9,R24
	.dbline 30
;  UBRRH = 0X00; //set baud rate hi
	out 0x20,R2
	.dbline 31
;  UCSRB = 0x90;//10010000
	ldi R24,144
	out 0xa,R24
	.dbline 32
;  UART_wp = 0;
	clr R3
	sts _UART_wp+1,R3
	sts _UART_wp,R2
	.dbline 33
;  read_pt = 0;
	sts _read_pt+1,R3
	sts _read_pt,R2
	.dbline -2
L1:
	.dbline 0 ; func end
	ret
	.dbend
	.area vector(rom, abs)
	.org 52
	jmp _uart0_rx_isr
	.area text(rom, con, rel)
	.dbfile E:\Program\gps\serial.c
	.dbfunc e uart0_rx_isr _uart0_rx_isr fV
	.even
_uart0_rx_isr::
	st -y,R2
	st -y,R3
	st -y,R24
	st -y,R25
	st -y,R30
	st -y,R31
	in R2,0x3f
	st -y,R2
	.dbline -1
	.dbline 38
; }
; 
; #pragma interrupt_handler uart0_rx_isr:14
; void uart0_rx_isr(void)
; {
	.dbline 40
;      //uart has received a character in UDR
; 	if (count<max)
	lds R24,_count
	lds R25,_count+1
	cpi R24,0
	ldi R30,4
	cpc R25,R30
	brge L3
	.dbline 42
; 	/* read the received data */
; 	{
	.dbline 43
; 	    rcv_buf[UART_wp++]=UDR; /* store received data in buffer */
	lds R2,_UART_wp
	lds R3,_UART_wp+1
	movw R24,R2
	adiw R24,1
	sts _UART_wp+1,R25
	sts _UART_wp,R24
	ldi R24,<_rcv_buf
	ldi R25,>_rcv_buf
	movw R30,R2
	add R30,R24
	adc R31,R25
	in R2,0xc
	std z+0,R2
	.dbline 44
; 	    count++;
	lds R24,_count
	lds R25,_count+1
	adiw R24,1
	sts _count+1,R25
	sts _count,R24
	.dbline 45
; 	}
L3:
	.dbline 48
	lds R24,_UART_wp
	lds R25,_UART_wp+1
	cpi R24,0
	ldi R30,4
	cpc R25,R30
	brne L5
	.dbline 49
	clr R2
	clr R3
	sts _UART_wp+1,R3
	sts _UART_wp,R2
L5:
	.dbline -2
L2:
	ld R2,y+
	out 0x3f,R2
	ld R31,y+
	ld R30,y+
	ld R25,y+
	ld R24,y+
	ld R3,y+
	ld R2,y+
	.dbline 0 ; func end
	reti
	.dbend
	.dbfunc e Read_buf _Read_buf fc
;           temp -> R16
	.even
_Read_buf::
	.dbline -1
	.dbline 61
; 	 
; 	/* calculate buffer index */
; 	if (UART_wp==max)
; 	   UART_wp = 0;   // full return to the start
; }
; 
; /*********************************************************************
; *                   read data from buffer
; description: 1 close interrupt 
;              2 whether there are data to be read
;              3 read data, and count--
;              4 return the data
; 			 5 rp point to next character
; **********************************************************************/
; char Read_buf(void)
; {
L8:
	.dbline 63
L9:
	.dbline 63
;     char temp;
; 	while ( !count);//if no data ,wait for new data
	lds R2,_count
	lds R3,_count+1
	tst R2
	brne X0
	tst R3
	breq L8
X0:
	.dbline 64
; 	count--;
	lds R24,_count
	lds R25,_count+1
	sbiw R24,1
	sts _count+1,R25
	sts _count,R24
	.dbline 65
; 	temp=rcv_buf[read_pt++];
	lds R2,_read_pt
	lds R3,_read_pt+1
	movw R24,R2
	adiw R24,1
	sts _read_pt+1,R25
	sts _read_pt,R24
	ldi R24,<_rcv_buf
	ldi R25,>_rcv_buf
	movw R30,R2
	add R30,R24
	adc R31,R25
	ldd R16,z+0
	.dbline 66
; 	if (read_pt==1024)
	lds R24,_read_pt
	lds R25,_read_pt+1
	cpi R24,0
	ldi R30,4
	cpc R25,R30
	brne L11
	.dbline 67
; 	read_pt=0;
	clr R2
	clr R3
	sts _read_pt+1,R3
	sts _read_pt,R2
L11:
	.dbline 68
; 	return ( temp);
	.dbline -2
L7:
	.dbline 0 ; func end
	ret
	.dbsym r temp 16 c
	.dbend
	.area bss(ram, con, rel)
	.dbfile E:\Program\gps\serial.c
_read_pt::
	.blkb 2
	.dbsym e read_pt _read_pt I
_UART_wp::
	.blkb 2
	.dbsym e UART_wp _UART_wp I
_rcv_buf::
	.blkb 1024
	.dbsym e rcv_buf _rcv_buf A[1024:1024]c
_count::
	.blkb 2
	.dbsym e count _count I