OpenHarmony南向開發案例：【智能體重秤】

一、簡介

本demo基于OpenHarmony3.1Beta版本開發，該樣例能夠接入數字管家應用，通過數字管家應用監測體重秤上報數據，獲得當前測量到的體重，身高，并在應用端形成一段時間內記錄的體重值，以折線圖的形式表現出來，根據計算的BMI值來提醒當前身體健康狀態，推送健康小知識。

1.交互流程

如上圖所示，智能體重稱整體方案原理圖可以大致分成：智能體重稱設備、數字管家應用、云平臺三部分。智能體重稱通過MQTT協議連接華為IOT物聯網平臺，從而實現命令的接收和屬性上報。

2.實物簡介

如上圖示，左邊為xr806模組，右邊為超聲波測距模塊，echo腳連接PA19，Triq腳連接PA20,Vcc腳連接5V電源，Gnd腳接地，

如上圖示，右邊為稱重模塊，clk腳接PB15，dt腳接PB14，vcc腳接5V，gnd腳接地，稱重傳感器紅色線接E+，黑色線接E-，白色線接A-，綠色線接A+

左邊xr806模塊左下角k1按鍵，長按k1按鍵不放，同時上電，4-5秒后松開按鍵，可以清除已保存得配網信息

xr806模塊，在設備正常工作后，按k1按鍵，可以初始化當前得重量為0，高度為0

3.實物操作體驗

####二、 快速上手

1.硬件準備

• xr806模組
• hcsr04超聲波模塊
• hx711稱重模塊帶支架托盤
• 預裝HarmonyOS手機一臺

2、環境準備

參照文檔: [XR806快速上手指導文檔]

3、編譯前準備

鴻蒙開發文檔參考：[qr23.cn/AKFP8k]

設備側代碼下載

下載方式：使用git 命令下載，指令如下（用戶也可以根據需要將該倉庫fork到自己的目錄下后進行下載）

cd ~
git clone git@gitee.com:openharmony-sig/knowledge_demo_smart_home.git

代碼拷貝

cp -rfa  ~/knowledge_demo_smart_home/dev/team_x  ~/openharmony/vendor/
cp -rfa  ~/knowledge_demo_smart_home/dev/third_party/iot_link  ~/openharmony/third_party/

SOC代碼下載替換

當前官方soc代碼由于DHCP暫未適配，所以暫時不支持AP模式，這時需要下載并替換之前SOC代碼。如果官方soc代碼已修復該問題，可忽略此步驟。

git clone https://gitee.com/moldy-potato-chips/xr806_-ap_mode.git
mv ~/openharmony/device/soc/allwinner ~/allwinner.org			// 不建議直接刪除，
cp -raf xr806_-ap_mode ~/openharmony/device/soc/allwinner

整合并修改完成后的目錄結構如下圖

修改文件

• 修改編譯依賴

打開 device/soc/allwinner/xradio/xr806/BUILD.gn，添加應用依賴(deps字段):

module_group(module_name) {
  modules = [
      "src",
      "project",
      "include",
  ]
  configs = [
    ":SdkLdCconfig",
  ]
  deps = [ "http://vendor/team_x/smart_weight_scale/demo_smart_weight_scale:smart_weight_scale" ]
}

• 修改編譯方式

將demo依賴的庫編譯方式(static_library)修改為(source_set):

具體依賴查看demo_smart_weight_scale目錄下的BUILD.gn:

deps = [
       "../../common/iot_wifi_xradio:iot_wifi",
       "../../common/iot_cloud:iot_cloud",
       "http://third_party/cJSON:cjson",
       "../../common/iot_boardbutton_xradio:iot_boardbutton",
       "../../common/iot_boardled_xradio:iot_boardled_xradio",
    ]

其中//third_party/cJSON目錄下的BUILD.gn建議參照下面的修改:

source_set("cJSON") {
  sources = [
    "cJSON.c",
    "cJSON_Utils.c",
  ]
  ldflags = [ "-lm" ]
}

third_party/iot_link目錄下的各級使用到的BUILD.gn也需要將編譯方式修改為source_set，或者將所有需要編譯的文件放在iot_link目錄的BUILD.gn中，如下：

source_set("iot_link") {
    sources = [
        "link_log/link_log.c",
        "link_misc/link_random.c",
        "link_misc/link_ring_buffer.c",
        "link_misc/link_string.c",
        "network/dtls/dtls_al/dtls_al.c",
        "network/dtls/mbedtls/mbedtls_port/dtls_interface.c",
        "network/dtls/mbedtls/mbedtls_port/mbed_port.c",
        "network/dtls/mbedtls/mbedtls_port/timing_alt.c",
        "network/mqtt/mqtt_al/mqtt_al.c",
        "network/mqtt/paho_mqtt/port/paho_mqtt_port.c",
        "network/mqtt/paho_mqtt/port/paho_osdepends.c",
        "network/mqtt/paho_mqtt/paho/MQTTClient-C/src/MQTTClient.c",
        "network/mqtt/paho_mqtt/paho/MQTTPacket/src/MQTTConnectClient.c",
        "network/mqtt/paho_mqtt/paho/MQTTPacket/src/MQTTConnectServer.c",
        "network/mqtt/paho_mqtt/paho/MQTTPacket/src/MQTTDeserializePublish.c",
        "network/mqtt/paho_mqtt/paho/MQTTPacket/src/MQTTFormat.c",
        "network/mqtt/paho_mqtt/paho/MQTTPacket/src/MQTTPacket.c",
        "network/mqtt/paho_mqtt/paho/MQTTPacket/src/MQTTSerializePublish.c",
        "network/mqtt/paho_mqtt/paho/MQTTPacket/src/MQTTSubscribeClient.c",
        "network/mqtt/paho_mqtt/paho/MQTTPacket/src/MQTTSubscribeServer.c",
        "network/mqtt/paho_mqtt/paho/MQTTPacket/src/MQTTUnsubscribeClient.c",
        "network/mqtt/paho_mqtt/paho/MQTTPacket/src/MQTTUnsubscribeServer.c",
        "oc_mqtt/oc_mqtt_al/oc_mqtt_al.c",
        "oc_mqtt/oc_mqtt_profile_v5/oc_mqtt_profile.c",
        "oc_mqtt/oc_mqtt_profile_v5/oc_mqtt_profile_package.c",
        "oc_mqtt/oc_mqtt_profile_v5/oc_mqtt_event.c",
        "oc_mqtt/oc_mqtt_tiny_v5/oc_mqtt_tiny.c",
        "oc_mqtt/oc_mqtt_tiny_v5/hmac.c",
        "queue/queue.c",
    ]
    
    cflags = [ "-Wno-unused-variable" ]
    cflags += [ "-Wno-unused-but-set-variable" ]
    cflags += [  "-Wno-sign-compare" ]
    cflags += [  "-Wno-unused-parameter" ]
    cflags += [  "-Wno-unused-function" ]

    ldflags = [ "-Wl,-rpath-link=//device/xradio/xr806/xr_skylark/lib" ]
    ldflags += [ "-lmbedtls" ]

    include_dirs = [
        "inc",
        "link_log",
        "link_misc",
        "queue",
        "oc_mqtt/oc_mqtt_tiny_v5",
        "oc_mqtt/oc_mqtt_profile_v5",
        "oc_mqtt/oc_mqtt_al",
        "network/dtls/mbedtls/mbedtls_port",
        "network/mqtt/paho_mqtt/port",
        "network/mqtt/paho_mqtt/paho/MQTTClient-C/src",
        "network/mqtt/paho_mqtt/paho/MQTTPacket/src",
        "http://third_party/mbedtls/include/",
        "http://third_party/mbedtls/include/",
        "http://third_party/cJSON",
        "http://kernel/liteos_m/components/cmsis/2.0",
        "http://device/xradio/xr806/xr_skylark/include/net/mbedtls-2.2.0/",
    ]

    defines = [
        "MQTTCLIENT_PLATFORM_HEADER=paho_osdepends.h",
        "WITH_DTLS",
        "MBEDTLS_AES_ROM_TABLES",
        "MBEDTLS_CONFIG_FILE="los_mbedtls_config_dtls.h"",
        "CONFIG_DTLS_MBEDTLS_CERT",
        "CONFIG_DTLS_MBEDTLS_PSK",
        "CFG_MBEDTLS_MODE=PSK_CERT",
        "CONFIG_OC_MQTT_TINY_ENABLE=1"
    ]
}

• 修改iot_link中的部分文件

1. third_party/iot_link/network/mqtt/paho_mqtt/port/paho_mqtt_port.c
   測試發現，當fd為0的時候，在執行recv時會立馬返回-1，因此做下面規避操作。

   static int __socket_connect(Network *n, const char *host, int port)
   {
   	...
   	int tmpfd = socket(AF_INET,SOCK_STREAM,0); // to skip fd = 0;
   	fd = socket(AF_INET,SOCK_STREAM,0);
   	if(fd == -1) {
   		return ret;
   	}
   	close(tmpfd);       // to skip fd = 0;
   	...
   }
   

   系統setsockopt函數未適配，因此需要做下面的修改：

   static int __socket_read(void *ctx, unsigned char *buf, int len, int timeout)
   {
   	int fd;
       int ret = 0;
   #if 0
   	struct timeval timedelay = {timeout / 1000, (timeout % 1000) * 1000};
       if(NULL== uf)
       {
           return ret;
       }
   
       fd = (int)(intptr_t)ctx;  ///< socket could be zero
   
       if (timedelay.tv_sec < 0 || (timedelay.tv_sec == 0 && timedelay.tv_usec <= 0))
       {
           timedelay.tv_sec = 0;
           timedelay.tv_usec = 100;
       }
   
       if(0 != setsockopt(fd,SOL_SOCKET,SO_RCVTIMEO,&timedelay,sizeof(struct timeval)))
       {
           return ret;  //could not support the rcv timeout
       }
       int bytes = 0;
       while (bytes < len) {
           int rc = recv(fd, &buf[bytes], (size_t)(len - bytes), 0);
           printf("[%s|%s|%d]fd = %d, rc = %dn", __FILE__,__func__,__LINE__, fd, rc);
           if (rc == -1) {
               if (errno != EAGAIN && errno != EWOULDBLOCK) {
                   bytes = -1;
               }
               break;
           } else if (rc == 0) {
               bytes = 0;
               break;
           } else {
               bytes += rc;
           }
       }
       return bytes;
   #else
   	int bytes = 0;
       fd_set fdset;
   
       struct timeval timedelay = {timeout / 1000, (timeout % 1000) * 1000};
       if(NULL== buf)
       {
           return ret;
       }
   
       fd = (int)(intptr_t)ctx;  ///< socket could be zero
   
       if (timedelay.tv_sec < 0 || (timedelay.tv_sec == 0 && timedelay.tv_usec <= 0))
       {
           timedelay.tv_sec = 0;
           timedelay.tv_usec = 100;
       }
       timedelay.tv_sec = 2;
       FD_ZERO(&fdset);
       FD_SET(fd, &fdset);
   
       ret = select(fd + 1, &fdset, NULL, NULL, &timedelay);
       if (ret > 0) {
           while (bytes < len) {
               int rc = recv(fd, &buf[bytes], (size_t)(len - bytes), 0);
    //         printf("[%s|%s|%d]fd = %d, rc = %d, errno=%d(%s)n", __FILE__,__func__,__LINE__, fd, rc,errno, strerror(errno));
               if (rc == -1) {
                   if (errno != EAGAIN && errno != EWOULDBLOCK) {
                       bytes = -1;
                   }
                   break;
               } else if (rc == 0) {
                   bytes = 0;
                   break;
               } else {
                   bytes += rc;
               }
           }
       }
   
       return bytes;
   #endif
   }
   

2. third_party/iot_link/network/dtls/mbedtls/mbedtls_port/dtls_interface.c
   在文件頂部添加打印函數定義以及添加mbedtls_calloc以及mbedtls_free的定義，否則編譯會提示錯誤：

   #define MBEDTLS_LOG LINK_LOG_DEBUG
   #ifndef mbedtls_calloc
   #define mbedtls_calloc  calloc
   #endif
   #ifndef mbedtls_free
   #define mbedtls_free  free
   #endif
   

   系統部分mbedtls接口不一致，固需要注釋部分接口代碼：

   mbedtls_ssl_context dtls_ssl_new(dtls_establish_info_s *info, char plat_type)
   {
   	...
   	if (info- >psk_or_cert == VERIFY_WITH_PSK)
       {
   /*
           if ((ret = mbedtls_ssl_conf_psk(conf,
                                           info- >v.p.psk,
                                           info- >v.p.psk_len,
                                           info- >v.p.psk_identity,
                                           strlen((const char *)info- >v.p.psk_identity))) != 0)
           {
               MBEDTLS_LOG("mbedtls_ssl_conf_psk failed: -0x%x", -ret);
               goto exit_fail;
           }
   */
       }
       ...
   }
   
   int dtls_shakehand(mbedtls_ssl_context *ssl, const dtls_shakehand_info_s *info)
   {
   	...
   	if (MBEDTLS_SSL_IS_CLIENT == info- >client_or_server)
       {
           ret = mbedtls_net_connect(server_fd, info- >u.c.host, info- >u.c.port, info- >udp_or_tcp);
           if( 0 != ret)
           {
               ret = MBEDTLS_ERR_NET_CONNECT_FAILED;
               goto exit_fail;
           }
       }
       else
       {
           //server_fd = (mbedtls_net_context*)atiny_net_bind(NULL, info- >u.s.local_port, MBEDTLS_NET_PROTO_UDP);
           ///< --TODO ,not implement yet
       }
   	...
   }
   
   void dtls_init(void)
   {
       (void)mbedtls_platform_set_calloc_free(calloc, free);
       (void)mbedtls_platform_set_snprintf(snprintf);
   //    (void)mbedtls_platform_set_printf(printf);
   }
   

   在iot_link/network/dtls/mbedtls/mbedtls_port/mbed_port.c文件中的dtls_imp_init()函數中，也需要注釋掉未實現的接口，否則編譯報錯：

   int dtls_imp_init(void)
   {
       int ret =-1;
   
       // (void)mbedtls_platform_set_calloc_free(calloc, free); 
       // (void)mbedtls_platform_set_snprintf(snprintf);
       // (void)mbedtls_platform_set_printf(printf);
       ret = dtls_al_install(&s_mbedtls_io);
   
       return ret;
   }
   

3. 在文件iot_link/network/mqtt/paho_mqtt/port/paho_osdepends.c中添加對應timersub和timeradd的實現(系統中未實現該函數)：

   // add this for "timersub" && "timeradd"
   #ifndef	timersub
   #define timersub(s,t,a) (void) ( (a)- >tv_sec = (s)- >tv_sec - (t)- >tv_sec, 
           ((a)- >tv_usec = (s)- >tv_usec - (t)- >tv_usec) < 0 && 
           ((a)- >tv_usec += 1000000, (a)- >tv_sec--) )
   #endif
   #ifndef	timeradd
   #define timeradd(s,t,a) (void) ( (a)- >tv_sec = (s)- >tv_sec + (t)- >tv_sec, 
           ((a)- >tv_usec = (s)- >tv_usec + (t)- >tv_usec) >= 1000000 && 
           ((a)- >tv_usec -= 1000000, (a)- >tv_sec++) )
   #endif
   

4. 編譯中會有部分頭文件提示找不到，這個時候直接將其注釋即可(iot_link/network/mqtt/paho_mqtt/port/paho_osdepends.h):

   #define INVALID_SOCKET SOCKET_ERROR
   // #include < sys/socket.h >
   #include < sys/param.h >
   #include < sys/time.h >
   // #include < netinet/in.h >
   // #include < netinet/tcp.h >
   // #include < arpa/inet.h >
   // #include < netdb.h >
   #include < stdio.h >
   #include < unistd.h >
   #include < errno.h >
   #include < fcntl.h >
   #include < string.h >
   #include < stdlib.h >
   #endif
   
   #if defined(WIN32)
   #include < Iphlpapi.h >
   #else
   // #include < sys/ioctl.h >
   // #include < net/if.h >
   #endif
   

5. 因為弱引用導致無法鏈接相關符號，因此需要注釋以下幾個文件中的弱引用。

   文件一 third_party/iot_link/network/dtls/dtls_al/dtls_al.c
   #if 0
   __attribute__((weak))  int dtls_imp_init(void)
   {
       LINK_LOG_DEBUG("%s:###please implement dtls by yourself####",__FUNCTION__);
       return -1;
   }
   #endif
   extern int dtls_imp_init(void);
   
   文件二 third_party/iot_link/network/mqtt/mqtt_al/mqtt_al.c
   #if 0
   __attribute__((weak))  int mqtt_imp_init(void)
   {
       LINK_LOG_DEBUG("%s:###please implement mqtt by yourself####",__FUNCTION__);
       return -1;
   }
   #endif
   extern int mqtt_imp_init(void);
   
   文件三 third_party/iot_link/oc_mqtt/oc_mqtt_al/oc_mqtt_al.c
   #if 0
   __attribute__ ((weak)) int oc_mqtt_imp_init(void)
   {
       LINK_LOG_DEBUG("%s:###please implement oc mqtt by yourself####",__FUNCTION__);
       return 0;
   }
   
   __attribute__ ((weak)) int oc_mqtt_demo_main(void)
   {
       LINK_LOG_WARN("Please implement the oc mqtt v5 demo yourself");
       return -1;
   }
   #endif
   extern int oc_mqtt_demo_main(void);
   

• 修改GPIO查找方式

因為GPIO框架修改了設備驅動注冊的管腳號，導致應用無法根據HCS的引腳操作對應的GPIO，此問題已經提issue，如果該問題已解決，可以忽略此步驟。

打開drivers/framework/support/platform/src/gpio/gpio_manager.c，將cntlr->start = start；注釋即可。

static int32_t GpioManagerAdd(struct PlatformManager *manager, struct PlatformDevice *device)
{
    uint16_t start;
    struct GpioCntlr *cntlr = CONTAINER_OF(device, struct GpioCntlr, device);

    if ((start = GpioCntlrQueryStart(cntlr, &manager- >devices)) >= GPIO_NUM_MAX) {
        PLAT_LOGE("GpioCntlrAdd: query range for start:%d fail:%d", cntlr- >start, start);
        return HDF_ERR_INVALID_PARAM;
    }

//    cntlr- >start = start;
    DListInsertTail(&device- >node, &manager- >devices);
    PLAT_LOGI("%s: start:%u count:%u", __func__, cntlr- >start, cntlr- >count);
    return HDF_SUCCESS;
}

• 將對應的驅動文件復制到drvier對應目錄：
  因為主倉代碼中未將對應的驅動文件合并到driver/adpater/platform對應的目錄下，固需要手動將文件拷貝到對應目錄。若主倉已合入，可忽略此步驟。

  // 拷貝gpio驅動
  cp -af device/soc/allwinner/xradio/drivers/gpio/gpio_xradio.* driver/adpater/platform/gpio
  
  // 修改driver/adpater/platform/gpio/BUILD.gn文件，加上gpio_xradio的編譯
  
  hdf_driver(module_name) {
    sources = []
    if (defined(LOSCFG_SOC_COMPANY_BESTECHNIC)) {
      sources += [ "gpio_bes.c" ]
    }
  
    if (defined(LOSCFG_SOC_COMPANY_ALLWINNER)) {
      sources += [ "gpio_xradio.c" ]
    }
  
    include_dirs = [ "." ]
  }
  

  為了節省ram資源，可以把無用的資源先關閉，如關閉內部codec，將 device/soc/allwinner/xradio/xr806/project/prj_config.h中的PRJCONF_INTERNAL_SOUNDCARD_EN設置為0，如下：

  /* Xradio internal codec sound card enable/disable */
  #define PRJCONF_INTERNAL_SOUNDCARD_EN   0
  

4、代碼編譯

#首先可以查看一下hb的版本，如果hb版本為0.4.4版本就不需要更新。

查看hb版本

hb --version

更新hb, 以下指令需要在openharmony SDK根目錄執行

pip3 uninstall ohos_build
pip3 install build/lite

編譯命令：
hb set  // 如果是第一次編譯，Input code path 命令行中鍵入"./" 指定OpenHarmony工程編譯根目錄后 回車，
如下圖所示，使用鍵盤上下鍵選中wifi_skylark

hb build // 如果需要全量編譯，可以添加-f 選項

生成的固件保存在out/xradio/smart_weight_scale目錄下

5、固件燒錄

參照文檔:[XR806快速上手指導文檔]

6、設備配網

1. 在設備上電前需準備好安裝了數字管家應用的HarmonyOS手機, 并在設置中開啟手機的NFC功能；
2. 寫設備NFC標簽;
3. 燒錄完成后，上電。開發者在觀察開發板上狀態LED燈以８Hz的頻率閃爍時，將手機上半部靠近開發板NFC標簽處(無NFC標簽的可用NFC貼紙替代)；
4. 碰一碰后手機將自動拉起數字管家應用并進入配網狀態;
5. 配網過程中需要 連接設備的AP熱點，然后填寫需要配置的wifi的密碼;
6. 最后點擊配置，手機會將ssid以及對應的密碼通過AP熱點發送到設備。

審核編輯 黃宇