Error - invalid conversion from 'char' to 'const char*', Not able to connect on pubnub server using node mcu
problem was in the declaration of API keys and channel on the above code

Here is the right code:-

const char * pubkey = "publisher key from your account";
const char * subkey = "subscriber key from your account";

const char * pubchannel = "demo_keyset";
const char * subchannel = "demo_keyset";