如何让Xbee使用Uart与树莓派对话

I have a XBee S2 connected to a Raspberry Pi using the serial port and am trying to use minicom on the Pi to communicate and can not get a response from the XBee. I have tried numerous baud rates but when I enter +++ to wake up the XBee nothing happens.I have a XBee S2 connected to a Raspberry Pi us