Цитата
Port 2: Port 2 is a 32-bit I/O port with individual direction controls for each bit. The
operation of port 2 pins depends upon the pin function selected via the Pin Connect
block. Pins 14 through 31 of this port are not available.
Port 3: Port 3 is a 32-bit I/O port with individual direction controls for each bit. The
operation of port 3 pins depends upon the pin function selected via the Pin Connect
block. Pins 0 through 24, and 27 through 31 of this port are not available.
из LPC2364/66/68/78 User manual стр. 91, стр.93
Может как раз на этих пинах и смотрите?