SWM Enable an analog input or other special function

The switch matrix enables functions that can only be assigned to one pin. Examples are analog inputs, all GPIO pins, and the debug SWD pins.

  • If you want to assign a GPIO pin to a pin on any LPC81x package, disable any special function available on this pin in the PINENABLE0 register and do not assign any movable function to it.

    By default, all pins except pins PIO0_2, PIO0_3, and PIO0_5 are assigned to GPIO.

  • For all other functions that are not in the table of movable functions, do the following:
    1. Locate the function in the pin description table in the data sheet. This shows the package pin for this function.
    2. Enable the function in the PINENABLE0 register. All other possible functions on this pins are now disabled.