Initial commit: CODESYS tree, integration docs, Node-RED scripts.

PLC application sources (NVL, rooms, boiler), HA/Node-RED integration guide, and NVL patch utilities.

Co-authored-by: Cursor <cursoragent@cursor.com>

codesys-tree/Device/Plc Logic/Application/3.Function Blocks/fb_boiler.st

@@ -0,0 +1,151 @@
+(* === DECLARATION === *)
+FUNCTION_BLOCK fb_boiler
+VAR_INPUT
+    // Control Commands
+    ha_on: BOOL;              // Home Assistant ON command
+    ha_off: BOOL;             // Home Assistant OFF command
+    schedule_on: BOOL;        // Scheduled ON
+    schedule_off: BOOL;       // Scheduled OFF
+    
+    // Safety
+    emergency_stop: BOOL;     // Emergency stop input
+    
+    // Configuration
+    max_on_time: TIME := T#8H; // Maximum ON time (default 8 hours)
+END_VAR
+VAR_OUTPUT
+    // Outputs
+    relay_control: BOOL;      // Control output to relay
+    
+    // Status
+    state: BOOL;              // Current state
+    on_time_seconds: DINT;    // Current ON time in seconds
+    remaining_seconds: DINT;  // Remaining time in seconds
+    
+    // Safety Status
+    emergency_active: BOOL;   // Emergency stop active
+    time_limit_reached: BOOL; // Time limit was reached
+    error_state: BOOL;        // Error flag
+    error_code: INT;          // Error code
+END_VAR
+VAR
+    // Internal State
+    internal_state: BOOL := FALSE;
+    last_state: BOOL := FALSE;
+    
+    // Edge Detection
+    r_trig_ha_on: R_TRIG;
+    r_trig_ha_off: R_TRIG;
+    r_trig_schedule_on: R_TRIG;
+    r_trig_schedule_off: R_TRIG;
+    r_trig_emergency: R_TRIG;
+    f_trig_emergency: F_TRIG;
+    
+    // Timers
+    on_timer: TON;            // Counts ON time
+    
+    // Time tracking
+    max_on_seconds: DINT;
+END_VAR
+
+(* === IMPLEMENTATION === *)
+// =====================================================
+// fb_boiler - Implementation
+// =====================================================
+// Priority (highest to lowest):
+// 1. Emergency Stop       - Immediate shutdown
+// 2. Time Limit Exceeded  - Auto shutdown
+// 3. OFF Commands         - Turn off
+// 4. ON Commands          - Turn on (if safe)
+// =====================================================
+
+// Calculate max time in seconds
+max_on_seconds := TIME_TO_DINT(max_on_time) / 1000;
+
+// Edge detection for commands
+r_trig_ha_on(CLK := ha_on);
+r_trig_ha_off(CLK := ha_off);
+r_trig_schedule_on(CLK := schedule_on);
+r_trig_schedule_off(CLK := schedule_off);
+r_trig_emergency(CLK := emergency_stop);
+f_trig_emergency(CLK := emergency_stop);
+
+// =====================================================
+// SAFETY CHECKS (highest priority)
+// =====================================================
+
+// Priority 1: Emergency Stop
+IF emergency_stop THEN
+    internal_state := FALSE;
+    emergency_active := TRUE;
+    error_state := TRUE;
+    error_code := 1;  // Emergency stop active
+    
+// Priority 2: Time Limit Check
+ELSIF on_timer.Q THEN
+    internal_state := FALSE;
+    time_limit_reached := TRUE;
+    error_state := TRUE;
+    error_code := 2;  // Time limit exceeded
+
+// =====================================================
+// CONTROL LOGIC (only when safe)
+// =====================================================
+ELSE
+    // Clear safety flags when emergency released
+    IF f_trig_emergency.Q THEN
+        emergency_active := FALSE;
+        error_state := FALSE;
+        error_code := 0;
+    END_IF;
+    
+    // Clear time limit flag when boiler turned off
+    IF NOT internal_state THEN
+        time_limit_reached := FALSE;
+        IF error_code = 2 THEN
+            error_state := FALSE;
+            error_code := 0;
+        END_IF;
+    END_IF;
+    
+    // Priority 3: OFF Commands (HA OFF or Schedule OFF)
+    IF r_trig_ha_off.Q OR r_trig_schedule_off.Q THEN
+        internal_state := FALSE;
+        
+    // Priority 4: ON Commands (HA ON or Schedule ON)
+    ELSIF (r_trig_ha_on.Q OR r_trig_schedule_on.Q) AND NOT time_limit_reached THEN
+        internal_state := TRUE;
+    END_IF;
+END_IF;
+
+// =====================================================
+// TIMER MANAGEMENT
+// =====================================================
+
+// ON timer - counts total ON time
+on_timer(
+    IN := internal_state AND NOT emergency_active,
+    PT := max_on_time
+);
+
+// Calculate current ON time in seconds
+IF internal_state THEN
+    on_time_seconds := TIME_TO_DINT(on_timer.ET) / 1000;
+    remaining_seconds := max_on_seconds - on_time_seconds;
+    IF remaining_seconds < 0 THEN
+        remaining_seconds := 0;
+    END_IF;
+ELSE
+    on_time_seconds := 0;
+    remaining_seconds := max_on_seconds;
+END_IF;
+
+// =====================================================
+// OUTPUT ASSIGNMENT
+// =====================================================
+
+// Relay control - only ON when state is ON and no emergency
+relay_control := internal_state AND NOT emergency_active;
+
+// State output
+state := internal_state;