一、环境

1. 添加rtl8720的库
   https://github.com/ambiot/ambd_arduino/raw/master/Arduino_package/package_realtek.com_amebad_index.json
2. 板子选择 BW16
   
3. 例子选择Wifi->ScanNetworksScanNetworks
   

二、修改

源码位置：C:\Users\Administrator\AppData\Local\Arduino15\packages\realtek\hardware\AmebaD\3.1.4

1. ：C:\Users\Administrator\AppData\Local\Arduino15\packages\realtek\hardware\AmebaD\3.1.4\libraries\WiFi\src\WiFi.h
   class WiFiClass中增加CHANNEL成员

   int32_t CHANNEL(uint8_t networkItem);
   

2. ：C:\Users\Administrator\AppData\Local\Arduino15\packages\realtek\hardware\AmebaD\3.1.4\libraries\WiFi\src\WiFi.cpp
   增加实现

   int32_t WiFiClass::CHANNEL(uint8_t networkItem)
   {
       return WiFiDrv::getCHANNELNetworks(networkItem);
   }
   

3. ：C:\Users\Administrator\AppData\Local\Arduino15\packages\realtek\hardware\AmebaD\3.1.4\cores\ambd\wifi_drv.h
   分别增加成员

   private:
      static int32_t _networkchannel[WL_NETWORKS_LIST_MAXNUM];
        
   public:
   	static int32_t getCHANNELNetworks(uint8_t networkItem);
   

4. ：C:\Users\Administrator\AppData\Local\Arduino15\packages\realtek\hardware\AmebaD\3.1.4\cores\ambd\wifi_drv.cpp
   加入下面3点修改

   头加声明
   int32_t    WiFiDrv::_networkchannel[WL_NETWORKS_LIST_MAXNUM] = {0};
   
   rtw_result_t WiFiDrv::wifidrv_scan_result_handler( rtw_scan_handler_result_t* malloced_scan_result )
   中，增加 _networkchannel[_networkCount] = record->channel; //将channel导入
   
   增加实现
   int32_t WiFiDrv::getCHANNELNetworks(uint8_t networkItem)
   {
       if (networkItem >= WL_NETWORKS_LIST_MAXNUM) {
           //return NULL;
           return 0;
       }
   
       return _networkchannel[networkItem];
   }
   

5. ：
   例子中增加

   Serial.print("\tChannel: ");
   Serial.print(WiFi.CHANNEL(thisNet));
   

三、效果

其中大于100的信道是5G信道