 <p><a href="https://github.com/dwelch67" rel="nofollow">https://github.com/dwelch67</a></p> <p>I have a number of lpc based examples. You are looking for the IODIR register, depending on the port and flavor of LPC, there are now what they call fast I/O registers. a one in a bit location means that pin is an output, a zero an input.</p>