Hi I am using 80c251tb with uvision2. i have installed mon251 (9600 bps , internal UART) on to the FLASH ROM. i am using COM1 for monitor communication while com2 for program downloading. when i try to debug my program using the monitor, i am unable to do so. uvision either gives an error 'unable to find free serial connection' (while it has a dedicated serial port to itself or simply stops the debugger saying ' DLL cancelled. Debug aborted'. Please help me out.