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void IOHIDKeyboardDevice::postKeyboardEvent(UInt8 key, bool keyDown)
{
    GenericKeyboardRpt *report = (GenericKeyboardRpt *)_report->getBytesNoCopy();
    UInt8		usbKey;
        
    if (!report)
        return;
        
    // Convert ADB scan code to USB
    if (! (usbKey = _adb2usb[key]))
        return;
    
    // Check if modifier
    if ((usbKey >= 0xe0) && (usbKey <= 0xe7))
    {
	SET_MODIFIER_BIT(report->modifiers, usbKey, keyDown);
    }
    else
    {
        for (int i=0; i<6; i++)
        {                
            if (report->keys[i] == usbKey)
            {
                if (keyDown) return;
                    
                for (int j=i; j<5; j++)
                    report->keys[j] = report->keys[j+1];
                    
                report->keys[5] = 0;
                break;
            }
                
            else if ((report->keys[i] == 0) && keyDown)
            {
                report->keys[i] = usbKey;
                break;
            }
        }
    }
        
    handleReport(_report);
}