I am using a MC68HC908QY4A MCU for a handheld device. There are 3 switches A, B, and C. A and B are momentary push button switches, C is a toggle on/off switch. I have setup a keyboard interrupt service routine. The keyboard triggering sensitivity bit is set to falling edge only for all 3 switches. Right now, whenever switch C is at LOW, switch A and B are disabled. Is there a way to have switch A and B are active when switch C at LOW state.