User API reference of the Human Interface Device Class. More...

Functions
usbStatus	USBH_HID_GetDeviceStatus (uint8_t instance)
	Get status of Human Interface Device.

int32_t	USBH_HID_Read (uint8_t instance, uint8_t *buf, int32_t len)
	Read data received from Human Interface Device.

int32_t	USBH_HID_Write (uint8_t instance, const uint8_t *buf, int32_t len)
	Write data to Human Interface Device.

int	USBH_HID_GetKeyboardKey (uint8_t instance)
	Retrieve first pending pressed keyboard key on HID Keyboard.

usbStatus	USBH_HID_GetMouseState (uint8_t instance, usbHID_MouseState *state)
	Retrieve state change since last call of this function.

void	USBH_HID_ParseReportDescriptor (uint8_t instance, uint8_t *ptr_hid_report_desc)
	Callback function called for parsing of the Human Interface Device report descriptor.

void	USBH_HID_DataReceived (uint8_t instance, uint32_t len)
	Callback function called when data is received from the Human Interface Device.

Description

User API reference of the Human Interface Device Class.

Function Documentation

void USBH_HID_DataReceived	(	uint8_t	instance,
		uint32_t	len
	)

Callback function called when data is received from the Human Interface Device.

Parameters

[in]	instance	instance index.
[in]	len	length of received data.

Returns: none.

The USBH_HID_DataReceived function enables programmers to analyse received data coming from an USB HID device. Implementing this function in user code overrides the library function that handles boot protocol device data reception. This is useful if the default HID functionality needs to be changed to support special HID devices.

usbStatus USBH_HID_GetDeviceStatus ( uint8_t instance )

Get status of Human Interface Device.

Parameters

[in] instance instance of HID Device.

Returns: status code that indicates the execution status of the function as defined with usbStatus.

The function USBH_HID_GetDeviceStatus checks whether the human interface device is connected and initialized.

The argument instance is specifying the device instance.

Code Example

void USBH_Thread (void const *arg) {
  char con    =  0;                          /* Connection status of keyboard */
 
  USBH_Initialize (0);                       /* Initialize USB Host 0         */
 
  while (1) {
    con = USBH_HID_GetDeviceStatus(0) == usbOK;  /* Get kbd connection status */
  //do something
  }
}

int32_t USBH_HID_GetKeyboardKey ( uint8_t instance )

Retrieve first pending pressed keyboard key on HID Keyboard.

Parameters

[in] instance instance of HID Device.

Returns

value of read character or no character received.

value >= 0: value of first received unread character
value -1: indicates no character was received

The function USBH_HID_GetKeyboardKey enables programmers to handle signals from an USB keyboard.

The argument instance is specifying the device instance.

Code Example

int main (void) {
  char cmdbuf [15];                          /* command input buffer          */
  int idx;                                   /* index for circular buffer     */
 
  osThreadCreate (osThread(USBH_Thread), NULL);
 
  timer_id = osTimerCreate(osTimer(timer_1ms), osTimerPeriodic, NULL);
  osTimerStart(timer_id, 1);
 
  clear_records ();                          /* initialize circular buffer    */
  printf ( menu );                           /* display command menu          */
 
  while (1)  {                               /* loop forever                  */
    if (getline (&cmdbuf[0], sizeof (cmdbuf)) == false)
      continue;
 
    switch (cmdbuf[i])  {                    /* proceed to command function   */
 
      case 'R':                              /* Read circular Buffer          */
        if ((idx = read_index (&cmdbuf[i+1])) == WRONGINDEX)  break;
        while (idx != sindex)  {             /* check end of table            */
          if (USBH_HID_GetKeyboardKey(0) == 0x1B) break;   /* ESC terminates  */
          if (save_record[idx].time.hour != 0xff)  {
            measure_display (save_record[idx]);  /* display record            */
            printf ("\n");
          }
          if (++idx == SCNT) idx = 0;        /* next circular buffer entry    */
        }
        break;
 
      default:                               /* Error Handling                */
        printf (ERROR_STR, "UNKNOWN COMMAND");
        printf (menu);                       /* display command menu          */
        break;
    }
  }
}

bool USBH_HID_GetMouseState	(	uint8_t	instance,
		usbHID_MouseState *	state
	)

Retrieve state change since last call of this function.

Parameters

[in]	instance	instance of HID Device.
[out]	state	pointer to mouse state usbHID_MouseState structure.

Returns: status code that indicates the execution status of the function as defined with usbStatus.

The function USBH_HID_GetMouseState enables programmers to handle signals from an USB mouse.

The argument instance is specifying the device instance.

The argument state is a pointer to the mouse state structure (usbHID_MouseState).

Code Example

#include "rl_usb.h"
 
void getmouse (void)  {
  ..
  if (USBH_HID_GetMouseState (0, &MouseState)) { // If mouse move
    ..
  }
)

void USBH_HID_ParseReportDescriptor	(	uint8_t	instance,
		uint8_t *	ptr_hid_report_desc
	)

Callback function called for parsing of the Human Interface Device report descriptor.

Parameters

[in]	instance	instance index.
[in]	ptr_hid_report_desc	pointer to HID report descriptor.

Returns: none.

The USBH_HID_ParseReportDescriptor function enables programmers to parse report descriptors of an USB HID device. Implementing this function in user code overrides the library function that handles boot protocol device report descriptor parsing. This is useful if the default HID functionality needs to be changed to support special HID devices.

int32_t USBH_HID_Read	(	uint8_t	instance,
		uint8_t *	buf,
		int32_t	len
	)

Read data received from Human Interface Device.

Parameters

[in]	instance	instance of HID Device.
[out]	buf	buffer that receives data.
[in]	len	maximum number of bytes to read.

Returns

number of bytes read or execution status.

value >= 0: number of bytes read
value < 0: error occurred, -value is execution status as defined with usbStatus

The function USBH_HID_Read retrieves the data sent by an USB HID device and stores it in a buffer.

The argument instance is specifying the device instance.

The argument buf is pointing to the location where the data will be returned (stored).

The argument len specifies the number of bytes to be read.

Code Example

#include "rl_usb.h"
 
void parse_HID (void)  {
  U8 data[16];
  ..
  if (USBH_HID_Read (0, &data, 2)) {  // If data received from HID device
    ..
  }
)

int32_t USBH_HID_Write	(	uint8_t	instance,
		const uint8_t *	buf,
		int32_t	len
	)

Write data to Human Interface Device.

Parameters

[in]	instance	instance of HID Device.
[in]	buf	data buffer containing data to write.
[in]	len	number of data bytes to write.

Returns

number of bytes accepted for writing or execution status.

value >= 0: number of bytes accepted for writing
value < 0: error occurred, -value is execution status as defined with usbStatus

The function USBH_HID_Write writes data from a buffer to an USB HID device.

The argument instance is specifying the device instance.

The argument buf is pointing to the location where the data will be written.

The argument len specifies the number of data bytes to be written.

Code Example

void USBH_Thread (void const *arg) {
  char con    =  0;                          /* Connection status of keyboard */
  char con_ex =  40;                         /* Previous connection status    
                                                + initial time in 100 ms   
                                                intervals for initial display */
 
  USBH_Initialize (0);                       /* Initialize USB Host 0         */
 
  while (1) {
    con = USBH_HID_GetDeviceStatus(0) == usbOK;  /* Get kbd connection status */
    if ((con ^ con_ex) & 1) {                /* If connection status changed  */
      if (con) {
        USBH_HID_Write (0,(uint8_t *)&out,1);/* Turn on NUM LED               */
        printf ("\nKeyboard connected\n");
      } else {
        printf ("\nKeyboard disconnected ...\n");
      }
    :
    }
    osDelay(100);
  }
}

Functions

Description

Function Documentation