I am trying to have my 8051 interrupt on a serial port and jump to an ISR. I have the serial port setup and the interrupt works...sort of.... The problem I have is that I want to use 0x03 (ctrl-c) as my user interrupt. For some reason, the serial window will not give me a RI when I hit CTRL-C....Any normal character for example "c" works fine and I get a recieve interrupt... Why will the Serial Window not give me an RI when I type in Ctrl-C? MG