X-Git-Url: http://git.linex4red.de/pub/USBasp.git/blobdiff_plain/a789619fbe2cd07347816cc5c168e8f904acca86..eb410869474e14ec5762a96b930bc200409b6915:/Demos/Device/ClassDriver/Keyboard/Keyboard.c

diff --git a/Demos/Device/ClassDriver/Keyboard/Keyboard.c b/Demos/Device/ClassDriver/Keyboard/Keyboard.c
index fb19d02d9..040aec453 100644
--- a/Demos/Device/ClassDriver/Keyboard/Keyboard.c
+++ b/Demos/Device/ClassDriver/Keyboard/Keyboard.c
@@ -37,6 +37,9 @@
 
 #include "Keyboard.h"
 
+/** Buffer to hold the previously generated Keyboard HID report, for comparison purposes inside the HID class driver. */
+uint8_t PrevKeyboardHIDReportBuffer[sizeof(USB_KeyboardReport_Data_t)];
+
 /** LUFA HID Class driver interface configuration and state information. This structure is
  *  passed to all HID Class driver functions, so that multiple instances of the same class
  *  within a device can be differentiated from one another.
@@ -49,6 +52,9 @@ USB_ClassInfo_HID_Device_t Keyboard_HID_Interface =
 
 				.ReportINEndpointNumber  = KEYBOARD_EPNUM,
 				.ReportINEndpointSize    = KEYBOARD_EPSIZE,
+
+				.PrevReportINBuffer      = PrevKeyboardHIDReportBuffer,
+				.PrevReportINBufferSize  = sizeof(PrevKeyboardHIDReportBuffer),
 			},
     };
 
@@ -129,10 +135,12 @@ ISR(TIMER0_COMPA_vect, ISR_BLOCK)
  *  \param[in] HIDInterfaceInfo  Pointer to the HID class interface configuration structure being referenced
  *  \param[in,out] ReportID  Report ID requested by the host if non-zero, otherwise callback should set to the generated report ID
  *  \param[out] ReportData  Pointer to a buffer where the created report should be stored
+ *  \param[out] ReportSize  Number of bytes written in the report (or zero if no report is to be sent
  *
- *  \return Number of bytes written in the report (or zero if no report is to be sent
+ *  \return Boolean true to force the sending of the report, false to let the library determine if it needs to be sent
  */
-uint16_t CALLBACK_HID_Device_CreateHIDReport(USB_ClassInfo_HID_Device_t* const HIDInterfaceInfo, uint8_t* const ReportID, void* ReportData)
+bool CALLBACK_HID_Device_CreateHIDReport(USB_ClassInfo_HID_Device_t* const HIDInterfaceInfo, uint8_t* const ReportID,
+                                         void* ReportData, uint16_t* ReportSize)
 {
 	USB_KeyboardReport_Data_t* KeyboardReport = (USB_KeyboardReport_Data_t*)ReportData;
 	
@@ -154,8 +162,9 @@ uint16_t CALLBACK_HID_Device_CreateHIDReport(USB_ClassInfo_HID_Device_t* const H
 	  
 	if (ButtonStatus_LCL & BUTTONS_BUTTON1)
 	  KeyboardReport->KeyCode[0] = 0x09; // F
-	  
-	return sizeof(USB_KeyboardReport_Data_t);
+	
+	*ReportSize = sizeof(USB_KeyboardReport_Data_t);
+	return false;
 }
 
 /** HID class driver callback function for the processing of HID reports from the host.