【道生物联TKB-620开发板试用】GPS模块定位数据无线传输接收端实现

1.说明

接上篇发送端，此篇主要实现将接收到的GPS坐标数据显示到另外一块TKB-620 OLED上，并且通过串口发给手机上位机，记录无人机运动轨迹，这个上位机后续实现。
2.代码实现

(1).模组数据接收解析实现，此处代码主要解析TK8620接收到的数据，并且将数据还原成"0001020304-N_S %s,latitude %s,E_W %s,longitude %s,\r\n",此处略其他AT指令处理代码，解析GPS定位数据具体实现如下:

`

//"AT+SENDB=0001020304-N_S %s,latitude %s,E_W %s,longitude %s,\\r\\n",
	//+DI: LEN 7, SLOT 0, SNR 13, RSSI -60, Data 0001020304-N_S %s,latitude %s,E_W %s,longitude %s,\\r\\n",
	case FSM_RCVDATA:     //7	    
		if (WorkUartRcv.USART_RX_STA.b.rdy) 
		{
			if (strstr((char *)WorkUartRcv.DataBuffer,"+DI"))  //找到帧头
			{
				RF_DEBUG("%s", WorkUartRcv.DataBuffer);
				pStrSnr = strstr((char *)WorkUartRcv.DataBuffer, "SNR ");
				pStrRssi = strstr((char *)WorkUartRcv.DataBuffer, "RSSI ");
				pStrData = strstr((char *)WorkUartRcv.DataBuffer, "Data ");
				if (pStrSnr) 
				{
					token = strtok(pStrSnr + 4, ",");
					if (token) 
						sys_param.snr = atoi(token);
				}

				if (pStrRssi) 
				{
					token = strtok(pStrRssi + 5, ",");
					if (token) 
						sys_param.rssi = atoi(token);
				}

				if (pStrData) 
				{
					token = strtok(pStrData + 5, "\\r\\n");
					if (token && !strncmp(token, "0001020304", strlen("0001020304"))) 
					{
						sys_param.rx_count++;
						token = strtok(pStrData + 15, "\\r\\n");
						if (token) 
						{
							txSideCnt = strtol(token, NULL, 16);
							if (sys_param.rx_count > txSideCnt) 
							{
								sys_param.rx_count = txSideCnt;
							}
							sys_param.rxPktLossRate = 100 - (((float)sys_param.rx_count / txSideCnt) * 100);
							sys_param.screen_refresh = 1;
						}
					}
					/***********GPS数据**********/
					pStrGPS = strtok(pStrData + 15, "\\r\\n");		
					memset(buffer,0,64);
					Str2Data(pStrGPS,(uint8_t*)buffer,strlen(pStrGPS));				
					pStrNS = strstr(buffer,"N_S:");
					//RF_DEBUG("buffer1:%s\\n", buffer);	
					pStrEW = strstr(buffer,"E_W:");
					//RF_DEBUG("buffer2:%s\\n", buffer);	
					pStrLatitude = strstr(buffer,"latitude:");
					//RF_DEBUG("buffer3:%s\\n", buffer);	
					pStrLongitude = strstr(buffer,"longitude:");
					//RF_DEBUG("buffer4:%s\\n", buffer);			
					if(pStrNS)
					{
						token = strtok(pStrNS + 4, ",");
						//RF_DEBUG("token:%s\\n", token);	
						if (token) 
						{
							memcpy(gpsData.N_S,token,strlen(token)>N_S_Length?N_S_Length:strlen(token));
							RF_DEBUG("gpsData.N_S:%s\\n", gpsData.N_S);	
							gpsData.isGetData = true;
							sys_param.screen_refresh = 1;
						}
						else
						{
							gpsData.isGetData = false;
							sys_param.screen_refresh = 0;
						}												
					}
					else
					{
						gpsData.isGetData = false;
						sys_param.screen_refresh = 0;					
					}
					

					if(pStrEW)
					{
						token = strtok(pStrEW + 4, ",");
						if (token) 
						{
							memcpy(gpsData.E_W,token,strlen(token)>E_W_Length?E_W_Length:strlen(token));
							RF_DEBUG("gpsData.E_W:%s\\n", gpsData.E_W);
							gpsData.isGetData = true;
							sys_param.screen_refresh = 1;
						}
						else
						{
							gpsData.isGetData = false;
							sys_param.screen_refresh = 0;
						}												
					}
					else
					{
						gpsData.isGetData = false;
						sys_param.screen_refresh = 0;					
					}					

					if(pStrLatitude)
					{
						token = strtok(pStrLatitude + 9, ",");
						if (token) 
						{
							memcpy(gpsData.latitude,token,strlen(token)>latitude_Length?latitude_Length:strlen(token));
							RF_DEBUG("gpsData.latitude:%s\\n", gpsData.latitude);
							gpsData.isGetData = true;
							sys_param.screen_refresh = 1;
						}
						else
						{
							gpsData.isGetData = false;
							sys_param.screen_refresh = 0;
						}												
					}
					else
					{
						gpsData.isGetData = false;
						sys_param.screen_refresh = 0;					
					}									

					if(pStrLongitude)
					{
						token = strtok(pStrLongitude + 10, ",");
						if (token) 
						{
							memcpy(gpsData.longitude,token,strlen(token)>longitude_Length?longitude_Length:strlen(token));
							RF_DEBUG("gpsData.longitude:%s\\n", gpsData.longitude);
							gpsData.isGetData = true;
							sys_param.screen_refresh = 1;
						}
						else
						{
							gpsData.isGetData = false;
							sys_param.screen_refresh = 0;
						}					
					}
					else
					{
						gpsData.isGetData = false;
						sys_param.screen_refresh = 0;					
					}

				}
			}
			WorkUartRcvClr();
		}
		break;

（2）OLED显示部分代码:
OLED要增加一个页面来显示GPS数据。

菜单新增代码:

`

{
		.screenIdx = 4,
		.screen_param = 
		{
			{.x_base = 0, .y_base = 0, .string = "5.GPS Display   ", .modifyPos = 0, .modify = 0},
			{.x_base = 0, .y_base = 1, .string = "Longitudes:     ", .modifyPos = 0, .modify = 0},
			{.x_base = 0, .y_base = 2, .string = "Invalid", .modifyPos = 0, .modify = 0},
			{.x_base = 0, .y_base = 3, .string = "Latitude:", .modifyPos = 0, .modify = 0},
			{.x_base = 0, .y_base = 4, .string = "Invalid", .modifyPos = 0, .modify = 0},
		}
	}

（3）.OLED显示代码:

`

case 4:	
		if(gpsData.isGetData)
		{
			xPos = show_param[screenIdx].screen_param[0].x_base;
			yPos = show_param[screenIdx].screen_param[0].y_base;
			pStr = show_param[screenIdx].screen_param[0].string;
			OLED_ShowString(xPos, yPos, pStr, 1);

			xPos = show_param[screenIdx].screen_param[1].x_base;
			yPos = show_param[screenIdx].screen_param[1].y_base;
			pStr = show_param[screenIdx].screen_param[1].string;
			OLED_ShowString(xPos, yPos, pStr, 1);
			//经度
			xPos = show_param[screenIdx].screen_param[2].x_base;
			yPos = show_param[screenIdx].screen_param[2].y_base;
            memset(str,0,12);
			strcat((char *)str, gpsData.E_W);
			strcat((char *)str, ":");
			strcat((char *)str, gpsData.longitude);
			pStr = str;
			OLED_ShowString(xPos, yPos, pStr, 1);
			
			xPos = show_param[screenIdx].screen_param[3].x_base;
			yPos = show_param[screenIdx].screen_param[3].y_base;
			pStr = show_param[screenIdx].screen_param[3].string;
			OLED_ShowString(xPos, yPos, pStr, 1);
			//纬度
			xPos = show_param[screenIdx].screen_param[4].x_base;
			yPos = show_param[screenIdx].screen_param[4].y_base;
			memset(str,0,12);
			strcat((char *)str, gpsData.N_S);
			strcat((char *)str, ":");
			strcat((char *)str, gpsData.latitude);
			pStr = str;
			OLED_ShowString(xPos, yPos, pStr, 1);
			gpsData.isGetData = false;
		}
		else
		{
			xPos = show_param[screenIdx].screen_param[0].x_base;
			yPos = show_param[screenIdx].screen_param[0].y_base;
			pStr = show_param[screenIdx].screen_param[0].string;
			OLED_ShowString(xPos, yPos, pStr, 1);

			xPos = show_param[screenIdx].screen_param[1].x_base;
			yPos = show_param[screenIdx].screen_param[1].y_base;
			pStr = show_param[screenIdx].screen_param[1].string;
			OLED_ShowString(xPos, yPos, pStr, 1);

			xPos = show_param[screenIdx].screen_param[2].x_base;
			yPos = show_param[screenIdx].screen_param[2].y_base;
			pStr = show_param[screenIdx].screen_param[2].string;
			OLED_ShowString(xPos, yPos, pStr, 1);
			
			xPos = show_param[screenIdx].screen_param[3].x_base;
			yPos = show_param[screenIdx].screen_param[3].y_base;
			pStr = show_param[screenIdx].screen_param[3].string;
			OLED_ShowString(xPos, yPos, pStr, 1);

			xPos = show_param[screenIdx].screen_param[4].x_base;
			yPos = show_param[screenIdx].screen_param[4].y_base;
			pStr = show_param[screenIdx].screen_param[4].string;
			OLED_ShowString(xPos, yPos, pStr, 1);
		}
		break;

3.结果展示


测试的时候我找了一条东西向的路走了一公里，经度数据还是有变化的，注意图片里面显示的坐标并非本人实际坐标，左边为发送端，右边为接收端。

4.开发心得

本次开发大量时间都都浪费到调试GPS定位数据接收解析，OLED数据显示上，大约花费了3个工作日实现了基本功能，无线通讯上基本没有花费时间，TurMass模块的优势在于无线通讯部分协议厂家全部开发好了，用户到手其实不用关心复杂的无线协议和模块寄存器配置，只需使用AT指令就能很快实现sub-1G无线通讯应用，相较于传统的LoRa和GFSK，具有快速上手和低成本的优势，因为LoRa和GFSK你要买第三方厂家封装好支持AT指令且支持快速组网的模组少说20元/pcs起步，目前已有第三方厂家生产的基于turmass技术的模组，如EBYTE的EWM-293-470，20dbm的版本目前报价不到16块/pcs，看了他的datasheet，似乎只是重新做了pcb layout，AT指令与道生提供的一模一样，对这个模组感兴趣可以买来玩玩，还有海凌科HLK-L08，也是基于tk8620实现。