Content originally posted in LPCWare by starblue on Tue Aug 25 08:59:57 MST 2015
You can switch them to GPIO by using the switch matrix (see the chapter in the user manual). You may also need to change something for I/O configuration (IOCON).
Of course you lose their functionality (reset, debug).
PIO0_10 and PIO0_11 are true open-drain pins, so you will need an external pull-up resistor (see the pin description in the user manual).