I'm currently creating a HID device with a STM32 to work with windows, and I struggle a lot with the Report. I always have an "this device cannot start - error 10, the report is not aligned with the bytes" (well it is directly translated from french, not sure if it could be say as so in english).
My report is as below
__ALIGN_BEGIN static uint8_t CUSTOM_HID_ReportDesc_FS[USBD_CUSTOM_HID_REPORT_DESC_SIZE] __ALIGN_END =
{
/* USER CODE BEGIN 0 */
0x05, 0x01, // UsagePage(Generic Desktop[0x0001])
0x09, 0x07, // UsageId(Keypad[0x0007])
// Block of usage
0xA1, 0x01, // Collection(Application)
0x85, 0x01, // ReportId(1)
0x05, 0x09, // UsagePage(Button[0x0009])
0x19, 0x01, // UsageIdMin(Button 1[0x0001])
0x29, 0x17, // UsageIdMax(Button 23[0x0017])
0x15, 0x00, // LogicalMinimum(0)
0x25, 0x01, // LogicalMaximum(1)
0x75, 0x17, // ReportSize(1)
0x95, 0x1, // ReportCount(23)
0x81, 0x02, // Input(Data, Variable, Absolute, NoWrap, Linear, PreferredState, NoNullPosition, BitField)
// usage page for other elements (leds or encoders)
0x95, 0x01, // ReportCount(1)
0x75, 0x06, // ReportSize(23)
0x81, 0x03, // Input(Constant, Variable, Absolute, NoWrap, Linear, PreferredState, NoNullPosition, BitField)
/* USER CODE END 0 */
0xC0 /* END_COLLECTION */
};
i defined my report as 31 Bytes length (same for the buffer).
But it does not work and as a noob i still do not know why..
thanks for looking
I have access to a PC now. I think your issue is that you have defined a 23-bit field followed by a 6-bit pad giving a total width of 29 bits which is not a multiple of 8-bits.
Try redefining your report descriptor as follows:
__ALIGN_BEGIN static uint8_t CUSTOM_HID_ReportDesc_FS[USBD_CUSTOM_HID_REPORT_DESC_SIZE] __ALIGN_END =
{
/* USER CODE BEGIN 0 */
0x05, 0x01, // UsagePage(Generic Desktop[0x0001])
0x09, 0x07, // UsageId(Keypad[0x0007])
// Block of usage
0xA1, 0x01, // Collection(Application)
0x85, 0x01, // ReportId(1)
0x05, 0x09, // UsagePage(Button[0x0009])
0x19, 0x01, // UsageIdMin(Button 1[0x0001])
0x29, 0x17, // UsageIdMax(Button 23[0x0017])
0x15, 0x00, // LogicalMinimum(0)
0x25, 0x01, // LogicalMaximum(1)
0x75, 0x01, // ReportSize(1)
0x95, 0x17, // ReportCount(23)
0x81, 0x02, // Input(Data, Variable, Absolute, NoWrap, Linear, PreferredState, NoNullPosition, BitField)
// usage page for other elements (leds or encoders)
0x95, 0x01, // ReportCount(1)
0x81, 0x03, // Input(Constant, Variable, Absolute, NoWrap, Linear, PreferredState, NoNullPosition, BitField)
/* USER CODE END 0 */
0xC0 /* END_COLLECTION */
};
Note that each report size is now 1 bit, but there are 23 button bits and 1 pad bit giving a total of 24 bits (3 bytes). The 1-byte report id prepends the report giving a total buffer size (i.e. structure size) of a nice round 4 bytes.
When I decode that using hidrdd I get:
//--------------------------------------------------------------------------------
// Decoded Application Collection
//--------------------------------------------------------------------------------
/*
05 01 (GLOBAL) USAGE_PAGE 0x0001 Generic Desktop Page
09 07 (LOCAL) USAGE 0x00010007 Keypad (Application Collection)
A1 01 (MAIN) COLLECTION 0x01 Application (Usage=0x00010007: Page=Generic Desktop Page, Usage=Keypad, Type=Application Collection)
85 01 (GLOBAL) REPORT_ID 0x01 (1)
05 09 (GLOBAL) USAGE_PAGE 0x0009 Button Page
19 01 (LOCAL) USAGE_MINIMUM 0x00090001 Button 1 Primary/trigger (Selector, On/Off Control, Momentary Control, or One Shot Control)
29 17 (LOCAL) USAGE_MAXIMUM 0x00090017 Button 23 (Selector, On/Off Control, Momentary Control, or One Shot Control)
15 00 (GLOBAL) LOGICAL_MINIMUM 0x00 (0) <-- Info: Consider replacing 15 00 with 14
25 01 (GLOBAL) LOGICAL_MAXIMUM 0x01 (1)
75 01 (GLOBAL) REPORT_SIZE 0x01 (1) Number of bits per field
95 17 (GLOBAL) REPORT_COUNT 0x17 (23) Number of fields
81 02 (MAIN) INPUT 0x00000002 (23 fields x 1 bit) 0=Data 1=Variable 0=Absolute 0=NoWrap 0=Linear 0=PrefState 0=NoNull 0=NonVolatile 0=Bitmap
95 01 (GLOBAL) REPORT_COUNT 0x01 (1) Number of fields
81 03 (MAIN) INPUT 0x00000003 (1 field x 1 bit) 1=Constant 1=Variable 0=Absolute 0=NoWrap 0=Linear 0=PrefState 0=NoNull 0=NonVolatile 0=Bitmap
C0 (MAIN) END_COLLECTION Application
*/
// All structure fields should be byte-aligned...
#pragma pack(push,1)
//--------------------------------------------------------------------------------
// Button Page inputReport 01 (Device --> Host)
//--------------------------------------------------------------------------------
typedef struct
{
uint8_t reportId; // Report ID = 0x01 (1)
// Collection: CA:Keypad
uint8_t BTN_KeypadButton1 : 1; // Usage 0x00090001: Button 1 Primary/trigger, Value = 0 to 1
uint8_t BTN_KeypadButton2 : 1; // Usage 0x00090002: Button 2 Secondary, Value = 0 to 1
uint8_t BTN_KeypadButton3 : 1; // Usage 0x00090003: Button 3 Tertiary, Value = 0 to 1
uint8_t BTN_KeypadButton4 : 1; // Usage 0x00090004: Button 4, Value = 0 to 1
uint8_t BTN_KeypadButton5 : 1; // Usage 0x00090005: Button 5, Value = 0 to 1
uint8_t BTN_KeypadButton6 : 1; // Usage 0x00090006: Button 6, Value = 0 to 1
uint8_t BTN_KeypadButton7 : 1; // Usage 0x00090007: Button 7, Value = 0 to 1
uint8_t BTN_KeypadButton8 : 1; // Usage 0x00090008: Button 8, Value = 0 to 1
uint8_t BTN_KeypadButton9 : 1; // Usage 0x00090009: Button 9, Value = 0 to 1
uint8_t BTN_KeypadButton10 : 1; // Usage 0x0009000A: Button 10, Value = 0 to 1
uint8_t BTN_KeypadButton11 : 1; // Usage 0x0009000B: Button 11, Value = 0 to 1
uint8_t BTN_KeypadButton12 : 1; // Usage 0x0009000C: Button 12, Value = 0 to 1
uint8_t BTN_KeypadButton13 : 1; // Usage 0x0009000D: Button 13, Value = 0 to 1
uint8_t BTN_KeypadButton14 : 1; // Usage 0x0009000E: Button 14, Value = 0 to 1
uint8_t BTN_KeypadButton15 : 1; // Usage 0x0009000F: Button 15, Value = 0 to 1
uint8_t BTN_KeypadButton16 : 1; // Usage 0x00090010: Button 16, Value = 0 to 1
uint8_t BTN_KeypadButton17 : 1; // Usage 0x00090011: Button 17, Value = 0 to 1
uint8_t BTN_KeypadButton18 : 1; // Usage 0x00090012: Button 18, Value = 0 to 1
uint8_t BTN_KeypadButton19 : 1; // Usage 0x00090013: Button 19, Value = 0 to 1
uint8_t BTN_KeypadButton20 : 1; // Usage 0x00090014: Button 20, Value = 0 to 1
uint8_t BTN_KeypadButton21 : 1; // Usage 0x00090015: Button 21, Value = 0 to 1
uint8_t BTN_KeypadButton22 : 1; // Usage 0x00090016: Button 22, Value = 0 to 1
uint8_t BTN_KeypadButton23 : 1; // Usage 0x00090017: Button 23, Value = 0 to 1
uint8_t : 1; // Pad
} inputReport01_t;
#pragma pack(pop)