Added support for special functions

Special functions are located in %ML1024 upward

webserver/core/ladder.h

@@ -70,6 +70,9 @@ extern IEC_UINT *int_memory[BUFFER_SIZE];
 extern IEC_DINT *dint_memory[BUFFER_SIZE];
 extern IEC_LINT *lint_memory[BUFFER_SIZE];
 
+//Special Functions
+extern IEC_LINT *special_functions[BUFFER_SIZE];
+
 //lock for the buffer
 extern pthread_mutex_t bufferLock;
 
@@ -110,6 +113,7 @@ bool pinNotPresent(int *ignored_vector, int vector_size, int pinNumber);
 extern uint8_t run_openplc;
 extern unsigned char log_buffer[1000000];
 extern int log_index;
+void handleSpecialFunctions();
 
 //server.cpp
 void startServer(int port);

webserver/core/main.cpp

@@ -39,6 +39,8 @@ extern int opterr;
 //extern int common_ticktime__;
 IEC_BOOL __DEBUG;
 
+IEC_LINT cycle_counter = 0;
+
 static int tick = 0;
 pthread_mutex_t bufferLock; //mutex for the internal buffers
 pthread_mutex_t logLock; //mutex for the internal log
@@ -148,6 +150,31 @@ void disableOutputs()
     }
 }
 
+//-----------------------------------------------------------------------------
+// Special Functions
+//-----------------------------------------------------------------------------
+void handleSpecialFunctions()
+{
+    //current time
+    struct tm *current_time;
+    time_t rawtime;
+    
+    tzset();
+    time(&rawtime);
+    current_time = localtime(&rawtime);
+    
+    rawtime = rawtime - timezone;
+    if (current_time->tm_isdst > 0) rawtime = rawtime + 3600;
+        
+    if (special_functions[0] != NULL) *special_functions[0] = rawtime;
+    
+    //number of cycles
+    cycle_counter++;
+    if (special_functions[1] != NULL) *special_functions[1] = cycle_counter;
+
+    //insert other special functions below
+}
+
 int main(int argc,char **argv)
 {
     unsigned char log_msg[1000];
@@ -232,6 +259,7 @@ int main(int argc,char **argv)
 		pthread_mutex_lock(&bufferLock); //lock mutex
 		updateCustomIn();
         updateBuffersIn_MB(); //update input image table with data from slave devices
+        handleSpecialFunctions();
 		config_run__(tick++); // execute plc program logic
 		updateCustomOut();
         updateBuffersOut_MB(); //update slave devices with data from the output image table