def set_pixel(self, x, y, state):
self.send_cmd("<STR_LIT:P>"+str(x+<NUM_LIT:1>)+"<STR_LIT:U+002C>"+str(y+<NUM_LIT:1>)+"<STR_LIT:U+002C>"+state)<EOL>
Set pixel at "x,y" to "state" where state can be one of "ON", "OFF"
        or "TOGGLE"