Add congestion helper

Author: nseidle

Firmware/RTK_Surveyor/src/BluetoothSerial/BluetoothSerial.cpp

@@ -885,4 +885,9 @@ bool BluetoothSerial::isReady(bool checkMaster, int timeout) {
     TickType_t xTicksToWait = timeout / portTICK_PERIOD_MS;
     return (xEventGroupWaitBits(_spp_event_group, SPP_RUNNING, pdFALSE, pdTRUE, xTicksToWait) & SPP_RUNNING) != 0;
 }
+
+bool BluetoothSerial::isCongested(){
+    return(!(xEventGroupGetBits(_spp_event_group) & SPP_CONGESTED));
+}
+
 #endif

Firmware/RTK_Surveyor/src/BluetoothSerial/BluetoothSerial.h

@@ -61,6 +61,8 @@ class BluetoothSerial: public Stream
         bool disconnect();
         bool unpairDevice(uint8_t remoteAddress[]);
 
+        bool isCongested();
+
     private:
         String local_name;