📺 BTT SKR Mini E3 with Fysetc V2.1 / MKS V3 / BTT V1 Mini 12864 (#23793)

Marlin/src/pins/stm32f1/pins_BTT_SKR_MINI_E3_common.h

       #define TFTGLCD_CS                    PA9
 
     #endif
+  
+  #elif ENABLED(FYSETC_MINI_12864_2_1)
+
+    #error "CAUTION! FYSETC_MINI_12864_2_1 / MKS_MINI_12864_V3 / BTT_MINI_12864_V1 requires wiring modifications. See 'pins_BTT_SKR_MINI_E3_common.h' for details. Comment out this line to continue."
+
+    /**
+     * FYSETC_MINI_12864_2_1 / MKS_MINI_12864_V3 / BTT_MINI_12864_V1 display pinout
+     *
+     *       Board                      Display
+     *       ------                     ------
+     * PB5  |10  9 | PA15       (BEEP) |10  9 | BTN_ENC
+     * PA9  | 8  7 | RESET      LCD_CS | 8  7 | LCD A0
+     * PA10 | 6  5 | PB9       LCD_RST | 6  5 | RED
+     * PB8  | 4  3 | PB15      (GREEN) | 4  3 | (BLUE)
+     * GND  | 2  1 | 5V            GND | 2  1 | 5V
+     *       ------                     ------
+     *        EXP1                       EXP1
+     *
+     *            ---                   ------
+     *       RST | 1 |          (MISO) |10  9 | SCK
+     * (RX2) PA2 | 2 |         BTN_EN1 | 8  7 | (SS)
+     * (TX2) PA3 | 3 |         BTN_EN2 | 6  5 | MOSI
+     *       GND | 4 |            (CD) | 4  3 | (RST)
+     *        5V | 5 |           (GND) | 2  1 | (KILL)
+     *            ---                   ------
+     *            TFT                    EXP2
+     *
+     * Needs custom cable:
+     *
+     *    Board             Display
+     *
+     *   EXP1-1 ----------- EXP1-1
+     *   EXP1-2 ----------- EXP1-2
+     *   EXP1-3 ----------- EXP2-6
+     *   EXP1-4 ----------- EXP1-5
+     *   EXP1-5 ----------- EXP2-8
+     *   EXP1-6 ----------- EXP1-6
+     *   EXP1-8 ----------- EXP1-8
+     *   EXP1-9 ----------- EXP1-9
+     *  EXP1-10 ----------- EXP1-7
+     *
+     *    TFT-2 ----------- EXP2-9
+     *    TFT-3 ----------- EXP2-5
+     *
+     * for backlight configuration see steps 2 (V2.1) and 3 in https://wiki.fysetc.com/Mini12864_Panel/
+     */
+
+    #define LCD_PINS_RS                     PA9     // CS
+    #define LCD_PINS_ENABLE                 PA3     // MOSI
+    #define LCD_BACKLIGHT_PIN               -1
+    #define NEOPIXEL_PIN                    PB8
+    #define LCD_CONTRAST                    255
+    #define LCD_RESET_PIN                   PA10
+
+    #define DOGLCD_CS                       PA9
+    #define DOGLCD_A0                       PB5
+    #define DOGLCD_SCK                      PA2
+    #define DOGLCD_MOSI                     PA3
+
+    #define BTN_ENC                         PA15
+    #define BTN_EN1                         PB9
+    #define BTN_EN2                         PB15
+
+    #define FORCE_SOFT_SPI
 
   #else
-    #error "Only CR10_STOCKDISPLAY, ZONESTAR_LCD, ENDER2_STOCKDISPLAY, MKS_MINI_12864, and TFTGLCD_PANEL_(SPI|I2C) are currently supported on the BIGTREE_SKR_MINI_E3."
+    #error "Only CR10_STOCKDISPLAY, ZONESTAR_LCD, ENDER2_STOCKDISPLAY, MKS_MINI_12864, TFTGLCD_PANEL_(SPI|I2C), FYSETC_MINI_12864_2_1, MKS_MINI_12864_V3, and BTT_MINI_12864_V1 are currently supported on the BIGTREE_SKR_MINI_E3."
   #endif
 
 #endif // HAS_WIRED_LCD