Added the channel parameter to the scan fucntion in order to select which channel to scan. (#3638)

The default value is 0 (= all channels) to preserve backward compatibility.

Author: ingframin

Diff for: libraries/WiFi/src/WiFiScan.cpp

@@ -54,7 +54,7 @@ void* WiFiScanClass::_scanResult = 0;
  * @param show_hidden   show hidden networks
  * @return Number of discovered networks
  */
-int16_t WiFiScanClass::scanNetworks(bool async, bool show_hidden, bool passive, uint32_t max_ms_per_chan)
+int16_t WiFiScanClass::scanNetworks(bool async, bool show_hidden, bool passive, uint32_t max_ms_per_chan, uint8_t channel)
 {
     if(WiFiGenericClass::getStatusBits() & WIFI_SCANNING_BIT) {
         return WIFI_SCAN_RUNNING;
@@ -70,7 +70,7 @@ int16_t WiFiScanClass::scanNetworks(bool async, bool show_hidden, bool passive,
     wifi_scan_config_t config;
     config.ssid = 0;
     config.bssid = 0;
-    config.channel = 0;
+    config.channel = channel;
     config.show_hidden = show_hidden;
     if(passive){
         config.scan_type = WIFI_SCAN_TYPE_PASSIVE;

Diff for: libraries/WiFi/src/WiFiScan.h

@@ -31,7 +31,7 @@ class WiFiScanClass
 
 public:
 
-    int16_t scanNetworks(bool async = false, bool show_hidden = false, bool passive = false, uint32_t max_ms_per_chan = 300);
+    int16_t scanNetworks(bool async = false, bool show_hidden = false, bool passive = false, uint32_t max_ms_per_chan = 300, uint8_t channel = 0);
 
     int16_t scanComplete();
     void scanDelete();