User Manual

XBee® Wi-Fi RF Modules
© 2012 Digi International, Inc. 3
Contents
XBee® Wi-Fi RF Module .......................................................................................................................... 1
1.Overview.............................................................................................................................................. 7
Specifications ...................................................................................................................................... 7
General Specifications .................................................................................................................... 7
RF Specifications ............................................................................................................................. 7
Electrical Specifications ................................................................................................................ 12
Serial Communications Specifications .......................................................................................... 12
UART ............................................................................................................................................. 12
SPI ................................................................................................................................................. 13
GPIO Specifications ........................................................................................................................... 13
Agency Approvals ............................................................................................................................. 14
Pin Signals ......................................................................................................................................... 14
Design Notes ..................................................................................................................................... 15
Power Supply ................................................................................................................................ 15
Recommended Pin Connections .................................................................................................. 16
Board Layout ................................................................................................................................ 16
Mounting Considerations – Xbee Wi-Fi Through-hole ................................................................. 19
2. RF Module Operation ....................................................................................................................... 20
Serial Communications ..................................................................................................................... 20
UART Communications ................................................................................................................. 20
SPI Communications ..................................................................................................................... 21
Serial Buffers .................................................................................................................................... 23
Serial Receive Buffer ..................................................................................................................... 23
Serial Transmit Buffer ................................................................................................................... 23
UART Flow Control ....................................................................................................................... 24
Serial Interface Protocols ................................................................................................................. 25
Transparent Operation ................................................................................................................. 25
API Operation ............................................................................................................................... 25
A Comparison of Transparent and API Operation ........................................................................ 26
Modes of Operation ......................................................................................................................... 27
Idle Mode ..................................................................................................................................... 27
Transmit Mode ............................................................................................................................. 27
Receive Mode ............................................................................................................................... 27
Command Mode ........................................................................................................................... 27