Fixed LowLevel Keyboard demo not saving the issued report only after it has been...

[pub/USBasp.git] / Demos / Device / ClassDriver / Keyboard / Keyboard.c

diff --git a/Demos/Device/ClassDriver/Keyboard/Keyboard.c b/Demos/Device/ClassDriver/Keyboard/Keyboard.c
index ea373a8..2918f5a 100644 (file)
--- a/Demos/Device/ClassDriver/Keyboard/Keyboard.c
+++ b/Demos/Device/ClassDriver/Keyboard/Keyboard.c
@@ -144,22 +144,34 @@ bool CALLBACK_HID_Device_CreateHIDReport(USB_ClassInfo_HID_Device_t* const HIDIn
        uint8_t JoyStatus_LCL    = Joystick_GetStatus();\r
        uint8_t ButtonStatus_LCL = Buttons_GetStatus();\r
 \r
+       static uint8_t PrevUsedKeyCodes;\r
+       uint8_t UsedKeyCodes = 0;\r
+       \r
        if (JoyStatus_LCL & JOY_UP)\r
-         KeyboardReport->KeyCode[0] = 0x04; // A\r
+         KeyboardReport->KeyCode[UsedKeyCodes++] = 0x04; // A\r
        else if (JoyStatus_LCL & JOY_DOWN)\r
-         KeyboardReport->KeyCode[0] = 0x05; // B\r
+         KeyboardReport->KeyCode[UsedKeyCodes++] = 0x05; // B\r
 \r
        if (JoyStatus_LCL & JOY_LEFT)\r
-         KeyboardReport->KeyCode[0] = 0x06; // C\r
+         KeyboardReport->KeyCode[UsedKeyCodes++] = 0x06; // C\r
        else if (JoyStatus_LCL & JOY_RIGHT)\r
-         KeyboardReport->KeyCode[0] = 0x07; // D\r
+         KeyboardReport->KeyCode[UsedKeyCodes++] = 0x07; // D\r
 \r
        if (JoyStatus_LCL & JOY_PRESS)\r
-         KeyboardReport->KeyCode[0] = 0x08; // E\r
+         KeyboardReport->KeyCode[UsedKeyCodes++] = 0x08; // E\r
          \r
        if (ButtonStatus_LCL & BUTTONS_BUTTON1)\r
-         KeyboardReport->KeyCode[0] = 0x09; // F\r
+         KeyboardReport->KeyCode[UsedKeyCodes++] = 0x09; // F\r
        \r
+       /* The host will ignore the device if we add a new keycode to the report while another keycode is currently\r
+        * being sent (i.e. the user has pressed another key while a key is already being pressed) - we need to intersperse\r
+        * the two reports with a zeroed report to force the host to accept the additional keys */\r
+       if (UsedKeyCodes != PrevUsedKeyCodes)\r
+       {\r
+               memset(KeyboardReport, sizeof(USB_KeyboardReport_Data_t), 0x00);\r
+               PrevUsedKeyCodes = UsedKeyCodes;\r
+       }\r
+\r
        *ReportSize = sizeof(USB_KeyboardReport_Data_t);\r
        return false;\r
 }\r