LPC-Link, the debug probe built into the original LPCXpresso board design, is only compatible with the LPCXpresso IDE (and the now discontinued Code Red Technologies Red Suite product).
If you want a debug probe suitable for use with another toolchain, such as Keil or IAR, then you should consider LPC-Link2 - either in standalone form or as built in to the LPCXpresso V2 boards.
