gfvalvo:
It already is a uint32_t. Check out the function's prototype in Esp.h:uint32_t getChipId();
Glad you said something. I'm quite new to this and so still relying heavily on the Arduino Reference pages. The switch...case page (switch...case - Arduino Reference) said that the allowed data types for the parameters were int & char. I took int to mean a 16-bit value as defined here: int - Arduino Reference
However, as per your tip, I just tried using ESP.getChipId() for the parameters and everything seems to work fine.
Thanks for helping me get rid of that clunky bit of code. 