Content originally posted in LPCWare by ktownsend on Fri Dec 16 01:26:34 MST 2011
You can use a UART to USB adapter (FTDI Cables, or many sites like Adafruit and Sparkfun have FT232 adapters for this), put the devices into ISP mode and then use the free tool FlashMagic to recover the device since enabling ISP mode will cause it to enter a special mode that will not execute the code on the flash.
You may even be able to connect with the debugger while in ISP mode and reprogram your flash, but I haven't tried this in LPCXpresso.
Just search for ISP in the UM and datasheet and you should find a description of how to enable it.