✨ LCD Backlight Timer (#23768)

Co-authored-by: Scott Lahteine <thinkyhead@users.noreply.github.com>

Marlin/Configuration.h

@@ -2820,7 +2820,7 @@
   #define BUTTON_DELAY_EDIT  50 // (ms) Button repeat delay for edit screens
   #define BUTTON_DELAY_MENU 250 // (ms) Button repeat delay for menus
 
-  //#define TOUCH_IDLE_SLEEP 300 // (secs) Turn off the TFT backlight if set (5mn)
+  //#define TOUCH_IDLE_SLEEP 300 // (s) Turn off the TFT backlight if set (5mn)
 
   #define TOUCH_SCREEN_CALIBRATION
 

Marlin/Configuration_adv.h

@@ -1277,6 +1277,11 @@
   #define FEEDRATE_CHANGE_BEEP_FREQUENCY 440
 #endif
 
+//
+// LCD Backlight Timeout
+//
+//#define LCD_BACKLIGHT_TIMEOUT 30 // (s) Timeout before turning off the backlight
+
 #if HAS_BED_PROBE && EITHER(HAS_MARLINUI_MENU, HAS_TFT_LVGL_UI)
   //#define PROBE_OFFSET_WIZARD       // Add a Probe Z Offset calibration option to the LCD menu
   #if ENABLED(PROBE_OFFSET_WIZARD)

Marlin/src/inc/SanityCheck.h

@@ -2857,6 +2857,14 @@ static_assert(Y_MAX_LENGTH >= Y_BED_SIZE, "Movement bounds (Y_MIN_POS, Y_MAX_POS
   #endif
 #endif
 
+#if LCD_BACKLIGHT_TIMEOUT
+  #if !HAS_ENCODER_ACTION
+    #error "LCD_BACKLIGHT_TIMEOUT requires an LCD with encoder or keypad."
+  #elif !PIN_EXISTS(LCD_BACKLIGHT)
+    #error "LCD_BACKLIGHT_TIMEOUT requires LCD_BACKLIGHT_PIN."
+  #endif
+#endif
+
 /**
  * Some boards forbid the use of -1 Native USB
  */

Marlin/src/lcd/language/language_en.h

@@ -402,6 +402,7 @@ namespace Language_en {
   LSTR MSG_ADVANCE_K_E                    = _UxGT("Advance K *");
   LSTR MSG_CONTRAST                       = _UxGT("LCD Contrast");
   LSTR MSG_BRIGHTNESS                     = _UxGT("LCD Brightness");
+  LSTR MSG_LCD_BKL_TIMEOUT                = _UxGT("LCD Sleep (s)");
   LSTR MSG_STORE_EEPROM                   = _UxGT("Store Settings");
   LSTR MSG_LOAD_EEPROM                    = _UxGT("Load Settings");
   LSTR MSG_RESTORE_DEFAULTS               = _UxGT("Restore Defaults");

Marlin/src/lcd/language/language_fr.h

@@ -335,6 +335,7 @@ namespace Language_fr {
   LSTR MSG_ADVANCE_K_E                    = _UxGT("Avance K *");
   LSTR MSG_BRIGHTNESS                     = _UxGT("Luminosité LCD");
   LSTR MSG_CONTRAST                       = _UxGT("Contraste LCD");
+  LSTR MSG_LCD_BKL_TIMEOUT                = _UxGT("Veille LCD (s)");
   LSTR MSG_STORE_EEPROM                   = _UxGT("Enregistrer config.");
   LSTR MSG_LOAD_EEPROM                    = _UxGT("Charger config.");
   LSTR MSG_RESTORE_DEFAULTS               = _UxGT("Restaurer défauts");

Marlin/src/lcd/marlinui.cpp

@@ -180,6 +180,15 @@ constexpr uint8_t epps = ENCODER_PULSES_PER_STEP;
   volatile int8_t encoderDiff; // Updated in update_buttons, added to encoderPosition every LCD update
 #endif
 
+#if LCD_BACKLIGHT_TIMEOUT
+  uint16_t MarlinUI::lcd_backlight_timeout; // Initialized by settings.load()
+  millis_t MarlinUI::backlight_off_ms = 0;
+  void MarlinUI::refresh_backlight_timeout() {
+    backlight_off_ms = lcd_backlight_timeout ? millis() + lcd_backlight_timeout * 1000UL : 0;
+    WRITE(LCD_BACKLIGHT_PIN, HIGH);
+  }
+#endif
+
 void MarlinUI::init() {
 
   init_lcd();
@@ -1033,14 +1042,18 @@ void MarlinUI::init() {
 
           reset_status_timeout(ms);
 
+          #if LCD_BACKLIGHT_TIMEOUT
+            refresh_backlight_timeout();
+          #endif
+
           refresh(LCDVIEW_REDRAW_NOW);
 
           #if LED_POWEROFF_TIMEOUT > 0
             if (!powerManager.psu_on) leds.reset_timeout(ms);
           #endif
-        }
+        } // encoder activity
 
-      #endif
+      #endif // HAS_ENCODER_ACTION
 
       // This runs every ~100ms when idling often enough.
       // Instead of tracking changes just redraw the Status Screen once per second.
@@ -1137,6 +1150,13 @@ void MarlinUI::init() {
           return_to_status();
       #endif
 
+      #if LCD_BACKLIGHT_TIMEOUT
+        if (backlight_off_ms && ELAPSED(ms, backlight_off_ms)) {
+          WRITE(LCD_BACKLIGHT_PIN, LOW); // Backlight off
+          backlight_off_ms = 0;
+        }
+      #endif
+
       // Change state of drawing flag between screen updates
       if (!drawing_screen) switch (lcdDrawUpdate) {
         case LCDVIEW_CLEAR_CALL_REDRAW:

Marlin/src/lcd/marlinui.h

@@ -275,6 +275,14 @@ public:
     FORCE_INLINE static void refresh_brightness() { set_brightness(brightness); }
   #endif
 
+  #if LCD_BACKLIGHT_TIMEOUT
+    #define LCD_BKL_TIMEOUT_MIN 1
+    #define LCD_BKL_TIMEOUT_MAX (60*60*18) // 18 hours max within uint16_t
+    static uint16_t lcd_backlight_timeout;
+    static millis_t backlight_off_ms;
+    static void refresh_backlight_timeout();
+  #endif
+
   #if HAS_DWIN_E3V2_BASIC
     static void refresh();
   #else

Marlin/src/lcd/menu/menu_configuration.cpp

@@ -541,6 +541,10 @@ void menu_configuration() {
   #if HAS_LCD_CONTRAST && LCD_CONTRAST_MIN < LCD_CONTRAST_MAX
     EDIT_ITEM_FAST(uint8, MSG_CONTRAST, &ui.contrast, LCD_CONTRAST_MIN, LCD_CONTRAST_MAX, ui.refresh_contrast, true);
   #endif
+  #if LCD_BACKLIGHT_TIMEOUT && LCD_BKL_TIMEOUT_MIN < LCD_BKL_TIMEOUT_MAX
+    EDIT_ITEM(uint16_4, MSG_LCD_BKL_TIMEOUT, &ui.lcd_backlight_timeout, LCD_BKL_TIMEOUT_MIN, LCD_BKL_TIMEOUT_MAX, ui.refresh_backlight_timeout);
+  #endif
+
   #if ENABLED(FWRETRACT)
     SUBMENU(MSG_RETRACT, menu_config_retract);
   #endif

Marlin/src/module/settings.cpp

@@ -391,6 +391,13 @@ typedef struct SettingsDataStruct {
   //
   uint8_t lcd_brightness;                               // M256 B
 
+  //
+  // LCD_BACKLIGHT_TIMEOUT
+  //
+  #if LCD_BACKLIGHT_TIMEOUT
+    uint16_t lcd_backlight_timeout;                     // (G-code needed)
+  #endif
+
   //
   // Controller fan settings
   //
@@ -607,6 +614,10 @@ void MarlinSettings::postprocess() {
   // Moved as last update due to interference with Neopixel init
   TERN_(HAS_LCD_CONTRAST, ui.refresh_contrast());
   TERN_(HAS_LCD_BRIGHTNESS, ui.refresh_brightness());
+
+  #if LCD_BACKLIGHT_TIMEOUT
+    ui.refresh_backlight_timeout();
+  #endif
 }
 
 #if BOTH(PRINTCOUNTER, EEPROM_SETTINGS)
@@ -1108,6 +1119,13 @@ void MarlinSettings::postprocess() {
       EEPROM_WRITE(lcd_brightness);
     }
 
+    //
+    // LCD Backlight Timeout
+    //
+    #if LCD_BACKLIGHT_TIMEOUT
+      EEPROM_WRITE(ui.lcd_backlight_timeout);
+    #endif
+
     //
     // Controller Fan
     //
@@ -2015,6 +2033,13 @@ void MarlinSettings::postprocess() {
         TERN_(HAS_LCD_BRIGHTNESS, if (!validating) ui.brightness = lcd_brightness);
       }
 
+      //
+      // LCD Backlight Timeout
+      //
+      #if LCD_BACKLIGHT_TIMEOUT
+        EEPROM_READ(ui.lcd_backlight_timeout);
+      #endif
+
       //
       // Controller Fan
       //
@@ -3040,6 +3065,13 @@ void MarlinSettings::reset() {
   //
   TERN_(HAS_LCD_BRIGHTNESS, ui.brightness = LCD_BRIGHTNESS_DEFAULT);
 
+  //
+  // LCD Backlight Timeout
+  //
+  #if LCD_BACKLIGHT_TIMEOUT
+    ui.lcd_backlight_timeout = LCD_BACKLIGHT_TIMEOUT;
+  #endif
+
   //
   // Controller Fan
   //