Get FolgerTech i3-2020 working again with 32-bit platforms (#7944)

Setup FolgerTech i3-2020 Configuration files as a reference platform for
32-Bit work.

Also fix MAX7219 debug lights on 32-bit platforms.

Marlin/src/config/examples/Folger Tech/i3-2020/Configuration.h

@@ -119,12 +119,13 @@
 // The following define selects which electronics board you have.
 // Please choose the name from boards.h that matches your setup
 #ifndef MOTHERBOARD
-  #define MOTHERBOARD BOARD_RAMPS_14_EFB
+  #define MOTHERBOARD BOARD_RAMPS_14_RE_ARM_EFB   // For people switching over to the Panucatt Re-ARM board
+//#define MOTHERBOARD BOARD_RAMPS_14_EFB          // For unmodified printers using Atmega-2560 and RAMPS boards.
 #endif
 
 // Optional custom name for your RepStrap or other custom machine
 // Displayed in the LCD "Ready" message
-#define CUSTOM_MACHINE_NAME "FT-2020"
+#define CUSTOM_MACHINE_NAME "FT-2020 v2"
 
 // Define this to set a unique identifier for this printer, (Used by some programs to differentiate between machines)
 // You can use an online service to generate a random UUID. (eg http://www.uuidgenerator.net/version4)
@@ -777,15 +778,15 @@
 // @section machine
 
 // The size of the print bed
-#define X_BED_SIZE 207
-#define Y_BED_SIZE 182
+//#define X_BED_SIZE 207    // For now...  use the old method of X_MIN_POS and X_MAX_POS to set X size
+//#define Y_BED_SIZE 182    // For now...  use the old method of Y_MIN_POS and Y_MAX_POS to set Y size
 
 // Travel limits (mm) after homing, corresponding to endstop positions.
 #define X_MIN_POS 6
 #define Y_MIN_POS 3
 #define Z_MIN_POS 0
-#define X_MAX_POS X_BED_SIZE
-#define Y_MAX_POS Y_BED_SIZE
+#define X_MAX_POS 207
+#define Y_MAX_POS 182
 #define Z_MAX_POS 175
 
 // If enabled, axes won't move below MIN_POS in response to movement commands.
@@ -1037,7 +1038,7 @@
 //
 // M100 Free Memory Watcher
 //
-#define M100_FREE_MEMORY_WATCHER // uncomment to add the M100 Free Memory Watcher for debug purpose
+//#define M100_FREE_MEMORY_WATCHER // uncomment to add the M100 Free Memory Watcher for debug purpose
 
 //
 // G20/G21 Inch mode support

Marlin/src/config/examples/Folger Tech/i3-2020/Configuration_adv.h

@@ -1391,11 +1391,15 @@
  * Fully assembled MAX7219 boards can be found on the internet for under $2(US).
  * For example, see https://www.ebay.com/sch/i.html?_nkw=332349290049
  */
-//#define MAX7219_DEBUG
+#define MAX7219_DEBUG
 #if ENABLED(MAX7219_DEBUG)
-  #define MAX7219_CLK_PIN   64  // 77 on Re-ARM       // Configuration of the 3 pins to control the display
-  #define MAX7219_DIN_PIN   57  // 78 on Re-ARM
-  #define MAX7219_LOAD_PIN  44  // 79 on Re-ARM
+//#define MAX7219_CLK_PIN   64  // on RAMPS       // Configuration of the 3 pins to control the display
+//#define MAX7219_DIN_PIN   57  // on RAMPS
+//#define MAX7219_LOAD_PIN  44  // on RAMPS
+
+  #define MAX7219_CLK_PIN   77 // on Re-ARM       // Configuration of the 3 pins to control the display
+  #define MAX7219_DIN_PIN   78 // on Re-ARM
+  #define MAX7219_LOAD_PIN  79 // on Re-ARM
 
   /**
    * Sample debug features

Marlin/src/feature/Max7219_Debug_LEDs.cpp

@@ -63,18 +63,38 @@ static uint8_t LEDs[8] = { 0 };
 
 void Max7219_PutByte(uint8_t data) {
   for (uint8_t i = 8; i--;) {
-    WRITE(MAX7219_CLK_PIN, LOW);       // tick
-    WRITE(MAX7219_DIN_PIN, (data & 0x80) ? HIGH : LOW);  // send 1 or 0 based on data bit
-    WRITE(MAX7219_CLK_PIN, HIGH);      // tock
+    #ifdef CPU_32_BIT                    // The 32-bit processors are so fast, a small delay in the code is needed
+                                         // to let the signal wires stabilize.
+      WRITE(MAX7219_CLK_PIN, LOW);       // tick
+      delayMicroseconds(5);
+      WRITE(MAX7219_DIN_PIN, (data & 0x80) ? HIGH : LOW);  // send 1 or 0 based on data bit
+      delayMicroseconds(5);
+      WRITE(MAX7219_CLK_PIN, HIGH);      // tock
+      delayMicroseconds(5);
+    #else
+      WRITE(MAX7219_CLK_PIN, LOW);       // tick
+      WRITE(MAX7219_DIN_PIN, (data & 0x80) ? HIGH : LOW);  // send 1 or 0 based on data bit
+      WRITE(MAX7219_CLK_PIN, HIGH);      // tock
+    #endif
+
     data <<= 1;
   }
 }
 
 void Max7219(const uint8_t reg, const uint8_t data) {
   WRITE(MAX7219_LOAD_PIN, LOW);  // begin
+  #ifdef CPU_32_BIT              // The 32-bit processors are so fast, a small delay in the code is needed
+    delayMicroseconds(5);        // to let the signal wires stabilize.
+  #endif
   Max7219_PutByte(reg);          // specify register
   Max7219_PutByte(data);         // put data
+  #ifdef CPU_32_BIT
+    delayMicroseconds(5);
+  #endif
   WRITE(MAX7219_LOAD_PIN, LOW);  // and tell the chip to load the data
+  #ifdef CPU_32_BIT
+    delayMicroseconds(5);
+  #endif
   WRITE(MAX7219_LOAD_PIN, HIGH);
 }
 
@@ -135,6 +155,7 @@ void Max7219_init() {
   SET_OUTPUT(MAX7219_CLK_PIN);
 
   OUT_WRITE(MAX7219_LOAD_PIN, HIGH);
+  delay(1);
 
   //initiation of the max 7219
   Max7219(max7219_reg_scanLimit, 0x07);
@@ -187,9 +208,13 @@ void Max7219_init() {
 void Max7219_idle_tasks() {
   #if ENABLED(MAX7219_DEBUG_PRINTER_ALIVE)
     static int debug_cnt = 0;
-    if (debug_cnt++ > 100) {
-      Max7219_LED_Toggle(7, 7);
-      debug_cnt = 0;
+    #ifdef CPU_32_BIT  
+      if (debug_cnt++ > 400) {
+    #else
+      if (debug_cnt++ > 100) {
+    #endif
+        Max7219_LED_Toggle(7, 7);
+        debug_cnt = 0;
     }
   #endif