XBIB-U-SP Digi International, XBIB-U-SP Datasheet - Page 9

• Manufacturer Part Number: XBIB-U-SP
• Description: Interface Development Tools USB/Xbee/Xbee-Pro Inf Brd SMT Pads
• Manufacturer: Digi International
• Type: USB to XBee / XBee-PROr

Specifications of XBIB-U-SP

• Rohs: yes
• Product: Development Boards
• Tool Is For Evaluation Of: XBee / XBee-PRO
• Interface Type: USB
• Operating Supply Voltage: 5 V

2. RF Module Operation
2.1. Serial Communications
2.1.1. UART Data Flow
Serial Data
The XBee/XBee-PRO OEM RF Modules interface to a host device through a logic-level asynchro-
nous serial port. Through its serial port, the module can communicate with any logic and voltage
compatible UART; or through a level translator to any serial device (For example: Through a Max-
Stream proprietary RS-232 or USB interface board).
Devices that have a UART interface can connect directly to the pins of the RF module as shown in
the figure below.
Figure 2‐01. System Data Flow Diagram in a UART‐interfaced environment
Data enters the module UART through the DI pin (pin 3) as an asynchronous serial signal. The sig-
nal should idle high when no data is being transmitted.
Each data byte consists of a start bit (low), 8 data bits (least significant bit first) and a stop bit
(high). The following figure illustrates the serial bit pattern of data passing through the module.
Figure 2‐02. UART data packet 0x1F (decimal number ʺ31ʺ) as transmitted through the RF module
The module UART performs tasks, such as timing and parity checking, that are needed for data
communications. Serial communications depend on the two UARTs to be configured with compati-
ble settings (baud rate, parity, start bits, stop bits, data bits).
© 2007 MaxStream, Inc.
(Low‐asserted signals distinguished with horizontal line over signal name.)
Example Data Format is 8‐N‐1 (bits ‐ parity ‐ # of stop bits)
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