Do you mean ALL of port C, or just the ONE pin PC2? In my version of PSDSoft express, you can use that as a combinatorial pin. On the other hand, if you mean the whole port, then it's a bit more difficult. Some of those pins are dedicated JTAG pins. I believe another thread on here talked about how you could reprogram those pins, but then you only get ONE attempt at it because once they're no longer JTAG pins, there's no way to reprogram the device if things don't work properly.
I use the JTAG pins and some General I/O in the rest of port C. just for example :When i try to configure PC7 as combinatoric pin ,it works. maybe I'Ve to upgrade my software? My present software version is:8.01 thanks
Perhaps an upgrade would help... for reference, I'm using 8.10. I haven't actually tried to use the pin as a combinatorial input, but I do at least have the selection in PSDSoft. Try an upgrade and let me know if that solves it. I'd be interested to know.