server: Z21 LanXLocoInfo support F29 to F31

Z21 Firmware 1.42 adds F29 to F31 to LAN_X_LOCO_INFO

server/src/hardware/protocol/z21/clientkernel.cpp

@@ -116,13 +116,13 @@ void ClientKernel::receive(const Message& message)
 
         case LAN_X_LOCO_INFO:
         {
-          const int n = message.dataLen() - 7;
-          if(n >= 7 && n <= 14)
+          if(message.dataLen() >= LanXLocoInfo::minMessageSize && message.dataLen() <= LanXLocoInfo::maxMessageSize)
           {
             const auto& reply = static_cast<const LanXLocoInfo&>(message);
 
+            const int maxFunc = reply.supportsF29F31() ? 31 : 28;
             bool val[31 + 1] = {};
-            const int maxFunc = (n >= 8) ? 31 : 28;
+
             for(int i = 0; i <= maxFunc; i++)
             {
               val[i] = reply.getFunction(i);

server/src/hardware/protocol/z21/messages.hpp

@@ -1123,6 +1123,9 @@ struct LanXLocoInfo : LanX
   static constexpr uint8_t flagF0 = 0x10;
   static constexpr uint8_t functionIndexMax = 28;
 
+  static constexpr uint8_t minMessageSize = 7 + 7;
+  static constexpr uint8_t maxMessageSize = 7 + 14;
+
   uint8_t addressHigh = 0; //db0
   uint8_t addressLow = 0;  //db1
   uint8_t db2 = 0;
@@ -1131,6 +1134,7 @@ struct LanXLocoInfo : LanX
   uint8_t f5f12 = 0;    //db5
   uint8_t f13f20 = 0;   //db6
   uint8_t f21f28 = 0;   //db7
+  uint8_t f29f31 = 0;   //db8 (firmware >= 1.42)
   uint8_t checksum = 0;
 
   LanXLocoInfo() :
@@ -1223,6 +1227,12 @@ struct LanXLocoInfo : LanX
     Z21::Utils::setSpeedStep(speedAndDirection, speedSteps(), value);
   }
 
+  inline bool supportsF29F31() const
+  {
+    //Firmware >= 1.42 adds db8 to store F29-F31 so dataLen increases to 15
+    return dataLen() >= 15;
+  }
+
   bool getFunction(uint8_t index) const
   {
     if(index == 0)
@@ -1235,6 +1245,8 @@ struct LanXLocoInfo : LanX
       return f13f20 & (1 << (index - 13));
     else if(index <= 28)
       return f21f28 & (1 << (index - 21));
+    else if(index <= 31 && supportsF29F31())
+      return f29f31 & (1 << (index - 29));
     else
       return false;
   }
@@ -1280,6 +1292,14 @@ struct LanXLocoInfo : LanX
       else
         f21f28 &= ~flag;
     }
+    else if(index <= 31 && supportsF29F31())
+    {
+      const uint8_t flag = (1 << (index - 29));
+      if(value)
+        f29f31 |= flag;
+      else
+        f29f31 &= ~flag;
+    }
   }
 
   inline void updateChecksum()
@@ -1288,7 +1308,8 @@ struct LanXLocoInfo : LanX
     LanX::updateChecksum(dataLen() - 6);
   }
 } ATTRIBUTE_PACKED;
-static_assert(sizeof(LanXLocoInfo) == 14);
+static_assert(sizeof(LanXLocoInfo) >= LanXLocoInfo::minMessageSize &&
+              sizeof(LanXLocoInfo) <= LanXLocoInfo::maxMessageSize);
 
 // Reply to LAN_X_GET_FIRMWARE_VERSION