fish xmodem.txt

c8051f310xmodembootloader.rar

// 从串口接收一字节
UI8_T serial_get_char(void)
{
	UI8_T cTm;

	while(!RI0);
	cTm = SBUF0;
	RI0 = 0;
	return cTm;
}

// 向串口发送一字节
void serial_put_char(UI8_T c)
{
	while(!TI0);
	TI0 = 0;
	SBUF0 = c;
}

// 等串口有数据
// 返回0=无数据,1=有数据
I8_T WaitChar(int tn)
{
	unsigned long ulTmo;
	while(tn--)
	{
		for (ulTmo=0; ulTmo<40000; ulTmo++)
		{
			if (RI0)return 1;
		}
		
		if(led_status == 0){
			P1_1 = 0; 
			P1_0 = 1;
		}else if(led_status == 2){
			P1_1 = 1; 
			P1_0 = 0;
		}else{
			P1_1 = 0; 
			P1_0 = 0;
		}

		led_status++;
		if(led_status >=4)
			led_status = 0;
	}
	return 0;
}



// 接收数据帧
int GetRecord(unsigned char blocknum, unsigned char *dest)
{
	UI8_T nextChar;
	I16_T size;
	UI16_T chk;

	nextChar = serial_get_char();
	if (nextChar != (255-blocknum))
	{
		return 0;
	}
	chk = 0;
	for (size = 0; size < XMODEM_DATA_SIZE; ++size)
	{
		nextChar = serial_get_char();
		chk = crc16_tab[((chk>>8) ^ nextChar) & 0xFF] ^ (chk << 8);
		dest[size] = nextChar;
	}
	nextChar = serial_get_char();
	if (nextChar != ((chk >> 8) & 0xFF)) return 0;
	nextChar = serial_get_char();
	if (nextChar != (chk& 0xFF)) return 0;
	return 1;
}

#define INVALID_STATE 0
#define WAITING_START 1
#define WAIT_SOH 2
#define RX_PACKET 3
#define RX_EOT 4
#define SEND_NAK 5

// xmodem协议接收文件
I8_T xmodem_rx(void)
{
	I8_T ntry;
	I8_T state;
	UI8_T nextChar;
	UI16_T i;

	ntry = 0;
	pack_counter = 1;
	real_pack_counter = 1;
	state = WAITING_START;

	while(1)
	{
		switch(state)
		{
			case WAITING_START:			// 请求传送
				serial_put_char('C');	// 发送请求符
				
				if (WaitChar(3))
				{
					nextChar = serial_get_char();	// 接收帧头
					if (nextChar == XMODEM_HEAD)
					{
						state = RX_PACKET;		// 收到帧头
					}
				}
				break;

			case WAIT_SOH:	// 等帧头
				nextChar = serial_get_char();	// 收帧头
				if (nextChar == XMODEM_HEAD)
				{
					state = RX_PACKET;
				}

				else if (nextChar == XMODEM_EOT)	// 收到终止符
				{
					state = RX_EOT;
					serial_put_char(XMODEM_ACK);	// 回送应答符
					return (1);						// 结束
				}

				else if (nextChar == XMODEM_CAN)	// 取消
				{
					return (1);
				}
				break;

			case RX_PACKET:		// 收帧
				nextChar = serial_get_char();		// 收帧计数
				if (nextChar != pack_counter)		// 帧计数是否正确
				{
					serial_put_char(XMODEM_CAN);	// 不正确,取消传送
					serial_put_char(XMODEM_CAN);
					serial_put_char(XMODEM_CAN);
					serial_put_char(XMODEM_CAN);
					return (-1);
				}
				if (GetRecord(pack_counter, frame_data)) //收数据
				{
					//处理接收到的数据
					if(real_pack_counter > 8 && real_pack_counter <= 448){
						for(i = 0; i < XMODEM_DATA_SIZE; i++){
							FLASH_ByteWrite(128*(real_pack_counter - 1) + i, frame_data[i]);
						}
					}

					//切换LED指示灯状态
					if(led_status == 0){
						P1_1 = 0; 
						P1_0 = 1;
					}else if(led_status == 2){
						P1_1 = 1; 
						P1_0 = 0;
					}else{
						P1_1 = 0; 
						P1_0 = 0;
					}

					if((pack_counter & 0x03) == 0)
						led_status++;
					
					if(led_status >=4)
						led_status = 0;

					++pack_counter;	
					++real_pack_counter;						// 计数加1
					ntry = 0;				
					state = WAIT_SOH;						// 等下一个帧
					serial_put_char(XMODEM_ACK);			// 发送应答
				}
				else	// 收数据错误
				{
					if (++ntry >9)	// 错误次数超出限制
					{
						serial_put_char(XMODEM_CAN);	// 取消传送
						serial_put_char(XMODEM_CAN);
						serial_put_char(XMODEM_CAN);
						serial_put_char(XMODEM_CAN);
						return (-1);
					}
					state = WAIT_SOH;
					serial_put_char(XMODEM_NAK);	// 请求重传
				}
				break;

			default:
				break;
		}
	}
	return 0;
}