diff --git a/Marlin/pins_AZTEEG_X1.h b/Marlin/pins_AZTEEG_X1.h
index 8f87a7eaa7..17290d1108 100644
--- a/Marlin/pins_AZTEEG_X1.h
+++ b/Marlin/pins_AZTEEG_X1.h
@@ -26,5 +26,4 @@
 
 #define BOARD_NAME "Azteeg X1"
 
-#define SANGUINOLOLU_V_1_2
-#include "pins_SANGUINOLOLU_11.h"
+#include "pins_SANGUINOLOLU_12.h"
diff --git a/Marlin/pins_MELZI.h b/Marlin/pins_MELZI.h
index 7c99373f3a..4f6ccb5e07 100644
--- a/Marlin/pins_MELZI.h
+++ b/Marlin/pins_MELZI.h
@@ -25,10 +25,5 @@
  */
 
 #define BOARD_NAME "Melzi"
-
-#ifdef __AVR_ATmega1284P__
-  #define LARGE_FLASH true
-#endif
-
-#define SANGUINOLOLU_V_1_2
-#include "pins_SANGUINOLOLU_11.h"
+#define IS_MELZI
+#include "pins_SANGUINOLOLU_12.h"
diff --git a/Marlin/pins_MELZI_CREALITY.h b/Marlin/pins_MELZI_CREALITY.h
index d66f589fea..b2f0cf8716 100644
--- a/Marlin/pins_MELZI_CREALITY.h
+++ b/Marlin/pins_MELZI_CREALITY.h
@@ -25,17 +25,12 @@
  */
 
 #define BOARD_NAME "Melzi (Creality)"
-
-#ifdef __AVR_ATmega1284P__
-  #define LARGE_FLASH true
-#endif
+#define IS_MELZI
+#include "pins_SANGUINOLOLU_12.h"
 
 // For the stock CR-10 use the REPRAP_DISCOUNT_FULL_GRAPHIC_SMART_CONTROLLER
 //   option for the display in Configuration.h
 
-#define SANGUINOLOLU_V_1_2
-#include "pins_SANGUINOLOLU_11.h"
-
 #undef LCD_SDSS
 #undef LED_PIN
 
diff --git a/Marlin/pins_MELZI_MAKR3D.h b/Marlin/pins_MELZI_MAKR3D.h
index bd86f59c01..556f9ce87f 100644
--- a/Marlin/pins_MELZI_MAKR3D.h
+++ b/Marlin/pins_MELZI_MAKR3D.h
@@ -25,10 +25,5 @@
  */
 
 #define BOARD_NAME "Melzi (ATmega1284)"
-
-#ifdef __AVR_ATmega1284P__
-  #define LARGE_FLASH true
-#endif
-
-#define SANGUINOLOLU_V_1_2
-#include "pins_SANGUINOLOLU_11.h"
+#define IS_MELZI
+#include "pins_SANGUINOLOLU_12.h"
diff --git a/Marlin/pins_SANGUINOLOLU_11.h b/Marlin/pins_SANGUINOLOLU_11.h
index 0691fb321a..4ed004549f 100644
--- a/Marlin/pins_SANGUINOLOLU_11.h
+++ b/Marlin/pins_SANGUINOLOLU_11.h
@@ -59,7 +59,9 @@
   #define BOARD_NAME "Sanguinololu <1.2"
 #endif
 
-#define IS_MELZI (MB(MELZI) || MB(MELZI_MAKR3D) || MB(MELZI_CREALITY))
+#ifdef __AVR_ATmega1284P__
+  #define LARGE_FLASH true
+#endif
 
 //
 // Limit Switches
@@ -116,7 +118,7 @@
 
 #endif
 
-#if MB(AZTEEG_X1) || MB(STB_11) || IS_MELZI
+#if MB(AZTEEG_X1) || MB(STB_11) || ENABLED(IS_MELZI)
   #define FAN_PIN           4 // Works for Panelolu2 too
 #endif
 
@@ -133,16 +135,25 @@
 //#define SDSS               24
 #define SDSS               31
 
-#if IS_MELZI
-  #define LED_PIN           27
+#if ENABLED(IS_MELZI)
+  #define LED_PIN          27
 #elif MB(STB_11)
   #define LCD_BACKLIGHT_PIN 17 // LCD backlight LED
 #endif
 
 #if DISABLED(SPINDLE_LASER_ENABLE) && ENABLED(SANGUINOLOLU_V_1_2) && !(ENABLED(ULTRA_LCD) && ENABLED(NEWPANEL))  // try to use IO Header
-  #define CASE_LIGHT_PIN         4   // MUST BE HARDWARE PWM  - see if IO Header is available
+  #define CASE_LIGHT_PIN     4 // MUST BE HARDWARE PWM  - see if IO Header is available
 #endif
 
+/**
+ * Sanguinololu 1.4 AUX pins:
+ *
+ *           PWM  TX1  RX1  SDA  SCL
+ *  12V  5V  D12  D11  D10  D17  D16
+ *  GND GND  D31  D30  D29  D28  D27
+ *            A4   A3   A2   A1   A0
+ */
+
 //
 // LCD / Controller
 //
@@ -152,7 +163,7 @@
 
     #if ENABLED(U8GLIB_ST7920) // SPI GLCD 12864 ST7920 ( like [www.digole.com] ) For Melzi V2.0
 
-      #if IS_MELZI // Melzi board
+      #if ENABLED(IS_MELZI)
         #define LCD_PINS_RS     30 // CS chip select /SS chip slave select
         #define LCD_PINS_ENABLE 29 // SID (MOSI)
         #define LCD_PINS_D4     17 // SCK (CLK) clock
@@ -160,7 +171,7 @@
         // Marlin so this can be used for BEEPER_PIN. You can use this pin
         // with M42 instead of BEEPER_PIN.
         #define BEEPER_PIN      27
-      #else        // Sanguinololu 1.3
+      #else        // Sanguinololu >=1.3
         #define LCD_PINS_RS      4
         #define LCD_PINS_ENABLE 17
         #define LCD_PINS_D4     30
@@ -210,7 +221,7 @@
 
   #if ENABLED(LCD_I2C_PANELOLU2)
 
-    #if IS_MELZI
+    #if ENABLED(IS_MELZI)
       #define BTN_ENC           29
       #define LCD_SDSS          30 // Panelolu2 SD card reader rather than the Melzi
     #else
@@ -280,7 +291,7 @@
      *                                   MS3  O|     |O  2A
      *                                /RESET  O|     |O  1A
      *                                /SLEEP  O|     |O  1B
-     *  SPINDLE_LASER_PWM_PIN  STEP  O|     |O  VDD
+     *  SPINDLE_LASER_PWM_PIN           STEP  O|     |O  VDD
      *  SPINDLE_LASER_ENABLE_PIN         DIR  O|     |O  GND
      *                                         -------
      *
diff --git a/Marlin/pins_SANGUINOLOLU_12.h b/Marlin/pins_SANGUINOLOLU_12.h
index 19c9e4939f..f648dce085 100644
--- a/Marlin/pins_SANGUINOLOLU_12.h
+++ b/Marlin/pins_SANGUINOLOLU_12.h
@@ -27,15 +27,14 @@
  *
  *  AZTEEG_X1
  *  MELZI
+ *  MELZI_CREALITY
  *  MELZI_MAKR3D
  *  SANGUINOLOLU_12
  *  STB_11
  */
 
-#define BOARD_NAME "Sanguinololu 1.2"
-
-#ifdef __AVR_ATmega1284P__
-  #define LARGE_FLASH true
+#ifndef BOARD_NAME
+  #define BOARD_NAME "Sanguinololu 1.2"
 #endif
 
 #define SANGUINOLOLU_V_1_2
diff --git a/Marlin/pins_STB_11.h b/Marlin/pins_STB_11.h
index 05fc40481d..de769fcb68 100644
--- a/Marlin/pins_STB_11.h
+++ b/Marlin/pins_STB_11.h
@@ -25,10 +25,4 @@
  */
 
 #define BOARD_NAME "STB V1.1"
-
-#ifdef __AVR_ATmega1284P__
-  #define LARGE_FLASH true
-#endif
-
-#define SANGUINOLOLU_V_1_2
-#include "pins_SANGUINOLOLU_11.h"
+#include "pins_SANGUINOLOLU_12.h"