Espruino USB HID GamePad - v0.1a ready ! ( may also be Bluetooth & RN42 ready .. )

Hi there !

I'll be writing the hc-05->RN42 guide the coming week ( with screenshots ;p )

on another subject, I uncovered dust from a STM32F3DISCOVERY yesterday & this time, took enough time to experiment with CubeMX-generated & modded stuff as well as flashing the thing.
( the goal is to familiarize myself enough with the stm32 environment without messing with one of my Espruino boards ;) ).
I succefully flashed a mouse HID & a keyboard+media HID to it, but for some reason, I can't get the GamePad HID to work as intended: it's detected as such, but I still have a byte-related trouble with the buttons ( the joysticks works fine ).

Thing is: I'm still wondering why the heck is doing so, since after multiple readings of the following code, I see no errors ? :|
Shouldn't it work if "sizeof(struct gamepadHID_t)" equals to "HID_EPIN_SIZE" ?

/* ==== main.c ==== */
/* USER CODE BEGIN 1 */
struct gamepadHID_t
  {
    //uint16_t buttons;
    uint8_t buttons1;
    uint8_t buttons2;
    int8_t left_x;
    int8_t left_y;
    int8_t right_x;
    int8_t right_y;
  };
  struct gamepadHID_t gamepadHID;
  //gamepadHID.buttons = 0b0000000000000000;
  gamepadHID.buttons1 = 0b00000000;
  gamepadHID.buttons2 = 0b00000000;
  gamepadHID.left_x = 0b00000000;
  gamepadHID.left_y = 0b00000000;
  gamepadHID.right_x = 0b00000000;
  gamepadHID.right_y = 0b00000000;
/* USER CODE END 1 */

/* USER CODE BEGIN 3 */
//gamepadHID.buttons = 0x55AA;
  //gamepadHID.buttons = 0b0000000011111111; // works ?!
  //gamepadHID.buttons = 0b0000000111111111; // also works ?!!
  //gamepadHID.buttons = 0b0111111111111111; // also works ..
  //gamepadHID.buttons = 0b1111111111111111;
  //gamepadHID.buttons1 = 0x55;
  //gamepadHID.buttons2 = 0xAA;
  //gamepadHID.buttons1 = 0b11111111;
  //gamepadHID.buttons2 = 0b11111111;
  gamepadHID.buttons1 = 0b01111111;
  gamepadHID.buttons2 = 0b01111111;
  gamepadHID.left_x = 127;
  gamepadHID.left_y = 127;
  gamepadHID.right_x = -127;
  gamepadHID.right_y = -127;
  //USBD_HID_SendReport(&hUsbDeviceFS, &gamepadHID, sizeof(struct gamepadHID_t));
  //USBD_HID_SendReport(&hUsbDeviceFS, &gamepadHID, sizeof(struct gamepadHID_t)+2);
  //USBD_HID_SendReport(&hUsbDeviceFS, &gamepadHID, 8);
  //USBD_HID_SendReport(&hUsbDeviceFS, &gamepadHID, sizeof(struct gamepadHID_t)+1);
  //HAL_Delay(30);
  //gamepadHID.buttons = 0;
  USBD_HID_SendReport(&hUsbDeviceFS, &gamepadHID, sizeof(struct gamepadHID_t));
  //HAL_Delay(30);
  //unsigned char data[HID_DATA_IN_PACKET_SIZE] = { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00};
  //unsigned char data[6] = { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00};
  //uint8_t data[6] = { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00};
  //uint8_t data[6] = { 0x00, 0x00, 127, 127, 127, 127}; // works with below T
  //uint8_t data[6] = { 127, 00, 127, 127, 127, 127}; // nope
  //USBD_HID_SendReport(data, 6);
  //USBD_HID_SendReport(&hUsbDeviceFS, &data, sizeof(data)); // "T" works, but 'implicit declaration' ..
/* USER CODE END 3 */

/* ==== usb_hid.h ==== */
/** @defgroup USBD_HID_Exported_Defines
  * @{
  */
[#define](https://forum.espruino.com/search/?q=%23define) HID_EPIN_ADDR                 0x81
[#define](https://forum.espruino.com/search/?q=%23define) HID_EPIN_SIZE                 0x06 /* max report size - for GamePad */
// ( .. )
[#define](https://forum.espruino.com/search/?q=%23define) HID_CUSTOM_REPORT_DESC_SIZE    46 /* GamePad HID report size */

/* ==== usb_hid.c ==== */
// TEF Edit: change 'bInterfaceSubClass' to 0 ( gamepad does not respect boot specifications )
//                & 'nInterfaceProtocol' to 5 ( gamepad )
__ALIGN_BEGIN static uint8_t USBD_HID_CfgDesc[USB_HID_CONFIG_DESC_SIZ]  __ALIGN_END =
{
// ( .. )
0x00,         /*bInterfaceSubClass : 1=BOOT, 0=no boot*/
0x05,         /*nInterfaceProtocol : 0=none, 1=keyboard, 2=mouse, 5=gamepad */
// ( .. )
// custom descriptor for GamePad
__ALIGN_BEGIN static uint8_t HID_CUSTOM_ReportDesc[HID_CUSTOM_REPORT_DESC_SIZE]  __ALIGN_END = {
  // 46 bytes
  0x05,   0x01,      // USAGE_PAGE (Generic Desktop)
  0x09,   0x05,      // USAGE (Game Pad) - Hut1_12v2.pdf p28 of 128
  0xA1,   0x01,      // COLLECTION (Application)

  0xA1,   0x00,      //   COLLECTION (Physical)
  0x05,   0x09,      //     USAGE_PAGE (Button)
  0x19,   0x01,      //     USAGE_MINIMUM (Button 1)
  0x29,   0x10,      //     USAGE_MAXIMUM (Button 16)

  0x15,   0x00,      //     LOGICAL_MINIMUM (0)
  0x25,   0x01,      //     LOGICAL_MAXIMUM (1)
  0x95,   0x10,      //     REPORT_COUNT (16)
  0x75,   0x01,      //     REPORT_SIZE (1)

  0x81,   0x02,      //     INPUT (Data,Var,Abs)

  0x05,   0x01,      //     USAGE_PAGE (Generic Desktop)
  0x09,   0x30,      //     USAGE (X)
  0x09,   0x31,      //     USAGE (Y)
  0x09,   0x32,      //     USAGE (Z) - Hut1_12v2.pdf p26 = represents R X-axis
  0x09,   0x33,      //     USAGE (Rx) - Hut1_12v2.pdf p26 = represents R Y-axis

  0x15,   0x81,      //     LOGICAL_MINIMUM (-127)
  0x25,   0x7F,      //     LOGICAL_MAXIMUM (127)
  0x75,   0x08,      //     REPORT_SIZE (8)
  0x95,   0x04,      //     REPORT_COUNT (4)

  0x81,   0x06,      //     INPUT (Data,Var,Abs) - absolute for joysticks ( != rel for mouse )
  0xC0,              //   END_COLLECTION

  0xc0               // END_COLLECTION
};

Once the above is fixed, one of the next steps is porting the Xbox360 controller code to it ( and then continue digging how to use an existing controller for the handshake part .. ).

As a side note, I tried but coouldn't get Espruino on the board ?
I used the Espruino_1V92 & Espruino_1V92.3 firmwares ( it seems 1V99 isn't available on the repos for the STM32F3DISCOVERY )
( I took not of the need for unplugging & replugging the 'USB USER' plug, but no /dev/tty<..> ever appear on my mac :/ )
The cli commands I used are the following:

// to flash any firmware generated from a 'make' call on CubeMX-generated files
st-flash --format ihex write ./build/stm32f3discovery_hidTest1.hex
// to flash Espruino firmware ? :|
st-flash erase // to clean stuff
st-flash write ./espruino_1v92/espruino_1v92.3_stm32f3discovery.bin 0x08000000