converting STM32F4 discovery USB mouse example to gamepad

[hsmeitink9]

Posted on August 28, 2013 at 23:05

I own a stm32f4 discovery board, for which a demonstration project can be downloaded here:

http://www.st.com/web/en/catalog/tools/PF257904

This demo consists of software to use the board as a usb hid mouse, using the accelerometer to control the mouse movement. I now want to change this into a gamepad, for now I'm leaving the other parts of the descriptor the same, so I only changed the usage from 0x09,0x02 (usage: mouse)

to 0x09 , 0x09 (usage: gamepad). (these values can be found in the usb_hid_core file)

But after this change the computer still sees it as a mouse, but one that is not functioning correctly. What else should I change?

Any help would be greatly appreciated, I have been trying all kinds of things, but nothing seems to work.

I have included the file that I linked to, the usb_hid_core file can be found in this file at this location: stsw-stm32068\STM32F4-Discovery_FW_V1.1.0\Libraries\STM32_USB_Device_Library\Class\hid\src #stm32f4-hid-mouse-gamepad

[hsmeitink9]

Posted on September 02, 2013 at 16:16

Nobody?

[Tesla DeLorean]

Posted on September 03, 2013 at 03:36

Evidently

It's also not appropriate to attach a copy of a 31 MB file to the forum, where a

http://www.st.com/st-web-ui/static/active/en/st_prod_software_internet/resource/technical/software/firmware/stsw-stm32068.zip

would be quite adequate. Your files, or a patch, would be far more effective.

[hsmeitink9]

Posted on September 03, 2013 at 17:19

Thanks for the tip.

I'm still stuck, i managed to alter the mouse descriptor, but can't get it to work as a gamepad, this is what my analyzer tells me:

http://hmsprojects.com/USB-invoerapparaat.html

[infoinfo991]

Posted on September 04, 2013 at 23:16

Try this descriptor instead

    0x05, 0x01,                    // USAGE_PAGE (Generic Desktop)    0x09, 0x05,                    // USAGE (Gamepad) // use 0x09, 0x04 for USAGE (Joystick)    0xa1, 0x01,                    // COLLECTION (Application)    0xa1, 0x00,                    //   COLLECTION (Physical)    0x09, 0x30,                    //     USAGE (X)    0x09, 0x31,                    //     USAGE (Y)    0x15, 0x81,                    //     LOGICAL_MINIMUM (-127)    0x25, 0x7f,                    //     LOGICAL_MAXIMUM (127)    0x75, 0x08,                    //     REPORT_SIZE (8)    0x95, 0x02,                    //     REPORT_COUNT (2)    0x81, 0x02,                    //     INPUT (Data,Var,Abs)    0xc0,                          //     END_COLLECTION    0xa1, 0x00,                    //   COLLECTION (Physical)    0x09, 0x32,                    //     USAGE (Z) // use 0x09, 0x30 for USAGE (X) // use 0x09, 0x33 for USAGE (Rx)    0x09, 0x35,                    //     USAGE (Rz) // use 0x09, 0x31 for USAGE (Y) // use 0x09, 0x34 for USAGE (Ry)    0x15, 0x81,                    //     LOGICAL_MINIMUM (-127)    0x25, 0x7f,                    //     LOGICAL_MAXIMUM (127)    0x75, 0x08,                    //     REPORT_SIZE (8)    0x95, 0x02,                    //     REPORT_COUNT (2)    0x81, 0x02,                    //     INPUT (Data,Var,Abs)    0xc0,                          //     END_COLLECTION    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)    0x75, 0x01,                    //     REPORT_SIZE (1)    0x95, 0x10,                    //     REPORT_COUNT (16)    0x81, 0x02,                    //     INPUT (Data,Var,Abs)    0xc0,                          //     END_COLLECTION    0xc0                           // END_COLLECTION

[hsmeitink9]

Posted on September 07, 2013 at 18:19

I tried it, but is still shows as a non functional mouse. I went trough all the files, but I can't find anything, is there a common reason why just changing the usage page and nothing else might not work?

[hsmeitink9]

Posted on September 22, 2013 at 14:06

Nobody?

[sebastien2]

Posted on April 12, 2014 at 22:56 Maybe you need to change the PID in the descriptor, to be sure the computer didn't use the last descriptor without reading the new one?

[sebastien2]

Posted on May 05, 2014 at 19:56

You need to change few others things to make it work as a gamepad. In usbd_hid_core.c you need to change :

     0x02,         //nInterfaceProtocol : 0=none, 1=keyboard, 2=mouse to the 0x00 value. Other thing, the report descriptor has to be changed, this is mine for a 3-buttons 2-axis gamepad, (you can change it to add button or anything else with the HIDtool) :     __ALIGN_BEGIN static uint8_t HID_MOUSE_ReportDesc[HID_MOUSE_REPORT_DESC_SIZE] __ALIGN_END =     {       0x05,   0x01, // USAGE_PAGE (Generic Desktop)       0x09,   0x05, // USAGE (Game Pad)       0xA1,   0x01, // COLLECTION (Application)         0xA1,   0x00, // COLLECTION (Physical)       0x05,   0x09, // USAGE_PAGE (Button)       0x19,   0x01, // USAGE_MINIMUM (Button 1)       0x29,   0x03, // USAGE_MAXIMUM (Button 3)         0x15,   0x00, // LOGICAL_MINIMUM (0)       0x25,   0x01, // LOGICAL_MAXIMUM (1)       0x95,   0x03, // REPORT_COUNT (3)       0x75,   0x01, // REPORT_SIZE (1)         0x81,   0x02, // INPUT (Data,Var,Abs)       0x95,   0x01, // REPORT_COUNT (1)       0x75,   0x05, // REPORT_SIZE (5)       0x81,   0x07, // INPUT (Cnst,Var,Rel)         0x05,   0x01, // USAGE_PAGE (Generic Desktop)       0x09,   0x30, // USAGE (X)       0x09,   0x31, // USAGE (Y)         0x15,   0x81, // LOGICAL_MINIMUM (-127)       0x25,   0x7F, // LOGICAL_MAXIMUM (127)       0x75,   0x08, // REPORT_SIZE (8)       0x95,   0x02, // REPORT_COUNT (2)         0x81,   0x02, // INPUT (Data,Var,Abs)       0xC0,   0xC0  // END_COLLECTION x2     }; The size of the report descriptor has changed so modify it in usbd_hid_core.c :     #define HID_MOUSE_REPORT_DESC_SIZE    48 Now the gamepad would be recognized. You only need to send a 3 bytes report (the first for the button, et the two others for the axis). For a test you could do it by using this code in stm32xx_it.c :     static uint8_t *USBD_HID_GetPos (void)     {     static uint8_t HID_Buffer[3] = {0};     static int8_t val_abs_x=0;     static uint8_t sens_x=0;       HID_Buffer[1] = 0;     HID_Buffer[2] = 0;          // X move     if (val_abs_x > 120)     {         sens_x = 0; // --         HID_Buffer[0]=0;     }     else if (val_abs_x < -120)     {         sens_x = 1; // ++         HID_Buffer[0]=1;     }          if (sens_x == 1)         val_abs_x = val_abs_x + 3;     else         val_abs_x = val_abs_x - 3;     HID_Buffer[1] = val_abs_x;     HID_Buffer[2] = 0;     return HID_Buffer;     } Anf finally change the line (in the same file) :       USBD_HID_SendReport (&USB_OTG_dev, buf, 4); to :       USBD_HID_SendReport (&USB_OTG_dev, buf, 3); This should work well on the STM32f4 discovery board. If not try change the PID by adding 1 (like 0x5711) in usbd_desc.c.