Empty serial without the need to edit system libraries

CD32ControllerUSB/CD32ControllerUSB.ino

@@ -23,11 +23,7 @@
 
 #include "Gamepad.h"
 
-enum Mode
-{
-  TwoButton,
-  CD32
-};
+#define BUTTON_READ_DELAY 300 // Button read delay in µs
 
 // Controller DB9 pins (looking face-on to the end of the plug):
 //
@@ -43,12 +39,22 @@ enum Mode
 //  3      3  PD0
 //  4      4  PD4
 //  5     A0  PF7
-//  6     6   PD7
+//  6      6  PD7 (Important: Connect this pin via a 220Ω resistor!)
 //  7     VCC
 //  8     GND
 //  9     A1  PF6
-//
-// Connect a slide switch to pins GND,GND and 2 (PD1)
+// -----------------
+// (Second controller port for future reference)
+//  1     15  PB1
+//  2     14  PB3
+//  3     16  PB2
+//  4     10  PB6
+//  5     A2  PF5
+//  6      7  PE6 (Important: Connect this pin via a 220Ω resistor!)
+//  7     VCC
+//  8     GND
+//  9     A3  PF4
+
 
 // Set up USB HID gamepad
 Gamepad_ Gamepad;
@@ -60,8 +66,12 @@ uint8_t axesPrev = 0;
 uint8_t buttons = 0;
 uint8_t buttonsPrev = 0;
 
-Mode mode = CD32;
-Mode modePrev = mode;
+// Timing
+long microsNow = 0;
+long microsButtons = 0;
+
+// CD32 controller detection
+uint8_t detection = 0;
 
 void setup()
 {
@@ -78,22 +88,15 @@ void setup()
 
 void loop()
 {
-  // Set mode from switch
-  (PIND & B00000010) ? mode = CD32 : mode = TwoButton;
+  // Get current time
+  microsNow = micros();
 
   // Read X and Y axes
   axes = ~(PIND & B00011101);
 
-  switch(mode)
+  // See if enough time has passed since last button read
+  if(microsNow > microsButtons+BUTTON_READ_DELAY)
   {
-    // Two button mode
-    case TwoButton:
-      buttons = ~( ((PIND & B10000000) >> 7) | ((PINF & B01000000) >> 5) | B11111100 );
-      break;
-
-    // CD32 button mode
-    case CD32:
-
     // Set pin 6 (clock, PD7) and pin 5 (latch, PF7) as output low
     PORTD &= ~B10000000; // low to disable internal pull-up (will become low when set as output)
     DDRD  |=  B10000000; // output
@@ -118,6 +121,10 @@ void loop()
     (PINF & B01000000) ? buttons &= ~B00010000 : buttons |= B00010000; // LTrig (5)
     sendClock();
     (PINF & B01000000) ? buttons &= ~B01000000 : buttons |= B01000000; // Play (7)
+    sendClock();
+    (PINF & B01000000) ? detection |= B00000001 : detection &= ~B00000001; // First detection bit (should be 1)
+    sendClock();
+    (PINF & B01000000) ? detection |= B00000010 : detection &= ~B00000010; // Second detection bit (should be 0)
 
     // Set pin 5 (latch, PF7) and pin 6 (clock, PD7) as input with pull-ups
     DDRF  &= ~B10000000; // input
@@ -126,7 +133,11 @@ void loop()
     PORTD |=  B10000000; // high to enable internal pull-up 
     delayMicroseconds(40);
 
-      break;
+    // Was a CD32 gamepad detected? If not, read button 1 and 2 "normally".
+    if(detection != B0000001)
+      buttons = ~( ((PIND & B10000000) >> 7) | ((PINF & B01000000) >> 5) | B11111100 );
+    
+    microsButtons = microsNow+400;
   }
 
   // Has any buttons changed state?
@@ -146,6 +157,7 @@ void loop()
     usbUpdate = true;
   }
 
+  // Update USB data if necessary
   if(usbUpdate)
   {
     Gamepad.send();
@@ -156,8 +168,8 @@ void loop()
 void sendClock()
 {
   // Send a clock pulse to pin 6 and wait
-  PORTD |=  B10000000;
+  PORTD |=  B10000000; // Enable pull-up
   delayMicroseconds(10);
-  PORTD &= ~B10000000;
+  PORTD &= ~B10000000; // Disable pull-up
   delayMicroseconds(40); 
 }

CD32ControllerUSB/Gamepad.cpp

@@ -143,3 +143,8 @@ void Gamepad_::send()
 {
   USB_Send(pluggedEndpoint | TRANSFER_RELEASE, &_GamepadReport, sizeof(GamepadReport));
 }
+
+uint8_t Gamepad_::getShortName(char *name)
+{
+  return 0;
+}

CD32ControllerUSB/Gamepad.h

@@ -66,6 +66,7 @@ class Gamepad_ : public PluggableUSBModule
   protected:
     int getInterface(uint8_t* interfaceCount);
     int getDescriptor(USBSetup& setup);
+    uint8_t getShortName(char *name);
     bool setup(USBSetup& setup);
     
     uint8_t epType[1];

CD32ControllerUSB/README.md

@@ -0,0 +1,16 @@
+# DaemonBite-CD32-USB
+## Introduction
+With this simple to build  adapter you can connect Amiga CD32 gamepads and Commodore/Amiga/Atari joysticks to a PC, Raspberry PI, MiSTer FPGA etc. The Arduino Pro Micro has very low lag when configured as a USB gamepad and it is plug n' play once it has been programmed. 
+
+## Parts you need
+- Arduino Pro Micro (ATMega32U4)
+- Male end of Mega Drive controller extension (or DSUB 9Pin Male connector and some wires)
+- 220Ω resistor
+- Heat shrink tube (Ø ~20mm)
+- Micro USB cable
+
+## Wiring
+![Assemble1](images/cd32-usb-adapter-wiring.png)
+
+## License
+This project is licensed under the GNU General Public License v3.0.

SegaControllerUSB/Gamepad.cpp

@@ -143,3 +143,8 @@ void Gamepad_::send()
 {
   USB_Send(pluggedEndpoint | TRANSFER_RELEASE, &_GamepadReport, sizeof(GamepadReport));
 }
+
+uint8_t Gamepad_::getShortName(char *name)
+{
+  return 0;
+}

SegaControllerUSB/Gamepad.h

@@ -29,12 +29,6 @@
 #include <Arduino.h>
 #include "HID.h"
 
-// NOTE: To make this work on the MiSTer (or possibly other Linux distros), 
-// you need to edit USBDesc.h like follows. Change:
-// #define ISERIAL         3
-// to
-// #define ISERIAL         0
-
 // The numbers after colon are bit fields, meaning how many bits the field uses.
 // Remove those if there are problems
 typedef struct {
@@ -66,6 +60,7 @@ class Gamepad_ : public PluggableUSBModule
   protected:
     int getInterface(uint8_t* interfaceCount);
     int getDescriptor(USBSetup& setup);
+    uint8_t getShortName(char *name);
     bool setup(USBSetup& setup);
     
     uint8_t epType[1];

SegaTwoControllersUSB/Gamepad.cpp

@@ -143,3 +143,8 @@ void Gamepad_::send()
 {
   USB_Send(pluggedEndpoint | TRANSFER_RELEASE, &_GamepadReport, sizeof(GamepadReport));
 }
+
+uint8_t Gamepad_::getShortName(char *name)
+{
+  return 0;
+}

SegaTwoControllersUSB/Gamepad.h

@@ -29,12 +29,6 @@
 #include <Arduino.h>
 #include "HID.h"
 
-// NOTE: To make this work on the MiSTer (or possibly other Linux distros), 
-// you need to edit USBDesc.h like follows. Change:
-// #define ISERIAL         3
-// to
-// #define ISERIAL         0
-
 // The numbers after colon are bit fields, meaning how many bits the field uses.
 // Remove those if there are problems
 typedef struct {
@@ -66,6 +60,7 @@ class Gamepad_ : public PluggableUSBModule
   protected:
     int getInterface(uint8_t* interfaceCount);
     int getDescriptor(USBSetup& setup);
+    uint8_t getShortName(char *name);
     bool setup(USBSetup& setup);
     
     uint8_t epType[1];

SegaTwoControllersUSB/SegaTwoControllersUSB.ino

@@ -21,12 +21,6 @@
  *  
  */
 
-// NOTE: To make this work on the MiSTer (or possibly other Linux distros), 
-// you need to edit USBDesc.h like follows. Change:
-// #define ISERIAL         3
-// to
-// #define ISERIAL         0
-
 #include "SegaControllers32U4.h"
 #include "Gamepad.h"