I am using the serial port commands from http://www.opserver.de/ubb7/ubbthreads.php?ubb=showflat&Number=280484&Searchpage=1&Main=34315&Words=%22port_write_bytes%22&Search=true#Post280484
and need to get it to work apparently by converting my numbers to hex.

How can I convert a variable or char to a HEX format (eg 100 = 0x64)

thanks... or if you know why/how the serial code won't accurately accept my numbers.
(I have the incoming byte setup as an int on the MCU side, incomingByte = Serial.read();)