🔧 Fix SPI_FLASH_BACKUP flag (#27934)

Followup to #27373

Author: ellensp

Marlin/src/gcode/control/M993_M994.cpp

@@ -49,7 +49,8 @@ void GcodeSuite::M993() {
     W25QXX.SPI_FLASH_BufferRead(buf, addr, COUNT(buf));
     addr += COUNT(buf);
     card.write(buf, COUNT(buf));
-    if (addr % (COUNT(buf) * 10) == 0) SERIAL_CHAR('.');
+    if (!(addr % (COUNT(buf) * 10))) SERIAL_CHAR('.');
+    if (!(addr % (COUNT(buf) * 32))) hal.watchdog_refresh();
   }
   SERIAL_ECHOLNPGM(" done");
 
@@ -78,7 +79,8 @@ void GcodeSuite::M994() {
     card.read(buf, COUNT(buf));
     W25QXX.SPI_FLASH_BufferWrite(buf, addr, COUNT(buf));
     addr += COUNT(buf);
-    if (addr % (COUNT(buf) * 10) == 0) SERIAL_CHAR('.');
+    if (!(addr % (COUNT(buf) * 10))) SERIAL_CHAR('.');
+    if (!(addr % (COUNT(buf) * 32))) hal.watchdog_refresh();
   }
   SERIAL_ECHOLNPGM(" done");
 

Marlin/src/inc/Conditionals-3-etc.h

@@ -677,7 +677,3 @@
 #if ANY(PID_DEBUG, PID_BED_DEBUG, PID_CHAMBER_DEBUG)
   #define HAS_PID_DEBUG 1
 #endif
-
-#if ALL(SPI_FLASH, HAS_MEDIA, MARLIN_DEV_MODE)
-  #define SPI_FLASH_BACKUP 1
-#endif

Marlin/src/inc/Conditionals-5-post.h

@@ -3593,3 +3593,8 @@
 #if ANY(AUTO_BED_LEVELING_UBL, M100_FREE_MEMORY_WATCHER, DEBUG_GCODE_PARSER, TMC_DEBUG, MARLIN_DEV_MODE, DEBUG_CARDREADER, M20_TIMESTAMP_SUPPORT, HAS_STM32_UID)
   #define NEED_HEX_PRINT 1
 #endif
+
+// SPI Flash Backup
+#if ALL(SPI_FLASH, HAS_MEDIA, MARLIN_DEV_MODE)
+  #define SPI_FLASH_BACKUP 1
+#endif

Marlin/src/pins/stm32f4/pins_MKS_NEPTUNE_X_common.h

@@ -226,7 +226,7 @@
 #if ENABLED(SPI_FLASH)
   #define HAS_SPI_FLASH                        1
   #define SPI_DEVICE                           2
-  #define SPI_FLASH_SIZE               0x1000000
+  #define SPI_FLASH_SIZE               0x1000000  // 16MB
   #define SPI_FLASH_CS_PIN                  PB12
   #define SPI_FLASH_MOSI_PIN                PC3
   #define SPI_FLASH_MISO_PIN                PC2