A character is pipelined between two serial UARTs using a pair of XBee Series 1 Transcievers. Make sure to use software serial example code for the RedBot to avoid bricking your XBee. This expands on ...
Digi XBee-S6B module has three wireless systems: ZigBee/WiFi/IEEE 802.15.4. This project uses Wi-Fi wireless system. Sketch uses 25090 bytes (77%) of program storage space. Maximum is 32256 bytes.