OpenHarmony南向开发案例：【智能体重秤】

一、简介

本demo基于OpenHarmony3.1Beta版本开发，该样例能够接入数字管家应用，通过数字管家应用监测体重秤上报数据，获得当前测量到的体重，身高，并在应用端形成一段时间内记录的体重值，以折线图的形式表现出来，根据计算的BMI值来提醒当前身体健康状态，推送健康小知识。

1.交互流程

如上图所示，智能体重称整体方案原理图可以大致分成：智能体重称设备、数字管家应用、云平台三部分。智能体重称通过MQTT协议连接华为IOT物联网平台，从而实现命令的接收和属性上报。

2.实物简介

如上图示，左边为xr806模组，右边为超声波测距模块，echo脚连接PA19，Triq脚连接PA20,Vcc脚连接5V电源，Gnd脚接地，

如上图示，右边为称重模块，clk脚接PB15，dt脚接PB14，vcc脚接5V，gnd脚接地，称重传感器红色线接E+，黑色线接E-，白色线接A-，绿色线接A+

左边xr806模块左下角k1按键，长按k1按键不放，同时上电，4-5秒后松开按键，可以清除已保存得配网信息

xr806模块，在设备正常工作后，按k1按键，可以初始化当前得重量为0，高度为0

3.实物操作体验

####二、 快速上手

1.硬件准备

• xr806模组
• hcsr04超声波模块
• hx711称重模块带支架托盘
• 预装HarmonyOS手机一台

2、环境准备

参照文档: [XR806快速上手指导文档]

3、编译前准备

鸿蒙开发文档参考：[qr23.cn/AKFP8k]

设备侧代码下载

下载方式：使用git 命令下载，指令如下（用户也可以根据需要将该仓库fork到自己的目录下后进行下载）

cd ~
git clone [e-mail]:openharmony-sig/knowledge_demo_smart_home.git

代码拷贝

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代码下载替换

当前官方soc代码由于DHCP暂未适配，所以暂时不支持AP模式，这时需要下载并替换之前SOC代码。如果官方soc代码已修复该问题，可忽略此步骤。

git clone https://gitee.com/moldy-potato-chips/xr806_-ap_mode.git
mv ~/openharmony/device/soc/allwinner ~/allwinner.org			// 不建议直接删除，
cp -raf xr806_-ap_mode ~/openharmony/device/soc/allwinner

整合并修改完成后的目录结构如下图

修改文件

• 修改编译依赖

打开 device/soc/allwinner/xradio/xr806/BUILD.gn，添加应用依赖(deps字段):

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

• 修改编译方式

将demo依赖的库编译方式(static_library)修改为(source_set):

具体依赖查看demo_smart_weight_scale目录下的BUILD.gn:

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

其中//third_party/cJSON目录下的BUILD.gn建议参照下面的修改:

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

third_party/iot_link目录下的各级使用到的BUILD.gn也需要将编译方式修改为source_set，或者将所有需要编译的文件放在iot_link目录的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",
        "//third_party/mbedtls/include/",
        "//third_party/mbedtls/include/",
        "//third_party/cJSON",
        "//kernel/liteos_m/components/cmsis/2.0",
        "//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
   测试发现，当fd为0的时候，在执行recv时会立马返回-1，因此做下面规避操作。

   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;
   	...
   }
   

   系统setsockopt函数未适配，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
   在文件顶部添加打印函数定义以及添加mbedtls_calloc以及mbedtls_free的定义，否则编译会提示错误：

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

   系统部分mbedtls接口不一致，固需要注释部分接口代码：

   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()函数中，也需要注释掉未实现的接口，否则编译报错：

   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中添加对应timersub和timeradd的实现(系统中未实现该函数)：

   // 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. 编译中会有部分头文件提示找不到，这个时候直接将其注释即可(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. 因为弱引用导致无法链接相关符号，因此需要注释以下几个文件中的弱引用。

   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

因为GPIO框架修改了设备驱动注册的管脚号，导致应用无法根据HCS的引脚操作对应的GPIO，此问题已经提issue，如果该问题已解决，可以忽略此步骤。

打开drivers/framework/support/platform/src/gpio/gpio_manager.c，将cntlr->start = start；注释即可。

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;
}

• 将对应的驱动文件复制到drvier对应目录：
  因为主仓代码中未将对应的驱动文件合并到driver/adpater/platform对应的目录下，固需要手动将文件拷贝到对应目录。若主仓已合入，可忽略此步骤。

  // 拷贝gpio驱动
  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的编译
  
  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 = [ "." ]
  }
  

  为了节省ram资源，可以把无用的资源先关闭，如关闭内部codec，将 device/soc/allwinner/xradio/xr806/project/prj_config.h中的PRJCONF_INTERNAL_SOUNDCARD_EN设置为0，如下：

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

4、代码编译

#首先可以查看一下hb的版本，如果hb版本为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根目录执行

pip3 uninstall ohos_build
pip3 install build/lite

编译命令：
hb set  // 如果是第一次编译，Input code path 命令行中键入"./" 指定OpenHarmony工程编译根目录后 回车，
如下图所示，使用键盘上下键选中wifi_skylark

hb build // 如果需要全量编译，可以添加-f 选项

生成的固件保存在out/xradio/smart_weight_scale目录下

5、固件烧录

参照文档:[XR806快速上手指导文档]

6、设备配网

1. 在设备上电前需准备好安装了数字管家应用的HarmonyOS手机, 并在设置中开启手机的NFC功能；
2. 写设备NFC标签;
3. 烧录完成后，上电。开发者在观察开发板上状态LED灯以８Hz的频率闪烁时，将手机上半部靠近开发板NFC标签处(无NFC标签的可用NFC贴纸替代)；
4. 碰一碰后手机将自动拉起数字管家应用并进入配网状态;
5. 配网过程中需要 连接设备的AP热点，然后填写需要配置的wifi的密码;
6. 最后点击配置，手机会将ssid以及对应的密码通过AP热点发送到设备。

审核编辑 黄宇