fix #346 limit tx power in japan

src/mesh/RF95Interface.cpp

@@ -41,6 +41,8 @@ bool RF95Interface::init()
     if (power > MAX_POWER) // This chip has lower power limits than some
         power = MAX_POWER;
 
+    limitPower();
+    
     iface = lora = new RadioLibRF95(&module);
 
 #ifdef RF95_TCXO

src/mesh/RadioInterface.cpp

@@ -136,6 +136,25 @@ void RadioInterface::applyModemConfig()
               power);
 }
 
+/**
+ * Some regulatory regions limit xmit power.
+ * This function should be called by subclasses after setting their desired power.  It might lower it
+ */
+void RadioInterface::limitPower()
+{
+    uint8_t maxPower = 255; // No limit
+
+#ifdef HW_VERSION_JP
+    maxPower = 13; // See https://github.com/meshtastic/Meshtastic-device/issues/346
+#endif
+    if (power > maxPower) {
+        DEBUG_MSG("Lowering transmit power because of regulatory limits\n");
+        power = maxPower;
+    }
+
+    DEBUG_MSG("Set radio: final power level=%d\n", power);
+}
+
 ErrorCode SimRadio::send(MeshPacket *p)
 {
     DEBUG_MSG("SimRadio.send\n");

src/mesh/RadioInterface.h

@@ -119,6 +119,12 @@ class RadioInterface : protected concurrency::NotifiedWorkerThread
 
     virtual void loop() {} // Idle processing
 
+    /**
+     * Some regulatory regions limit xmit power.
+     * This function should be called by subclasses after setting their desired power.  It might lower it
+     */
+    void limitPower();
+
     /**
      * Convert our modemConfig enum into wf, sf, etc...
      *

src/mesh/SX1262Interface.cpp

@@ -43,6 +43,9 @@ bool SX1262Interface::init()
 
     if (power > 22) // This chip has lower power limits than some
         power = 22;
+
+    limitPower();
+
     int res = lora.begin(freq, bw, sf, cr, syncWord, power, currentLimit, preambleLength, tcxoVoltage, useRegulatorLDO);
     DEBUG_MSG("SX1262 init result %d\n", res);