Digi International Inc XBEEPRO2 Manual Do Utilizador

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XBee®/XBee‐PRO® ZB RF Modules 
© 2011 Digi International, Inc.
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EM250 Pin Mappings
The following table shows how the EM250 pins are used on the XBee.
* NOTE: These lines may not go to the external XBEE pins of the module if the programmable secondary processor 
is populated.
Design Notes
The XBee modules do not specifically require any external circuitry or specific connections for proper 
operation. However, there are some general design guidelines that are recommended for help in 
troubleshooting and building a robust design.
Power Supply Design
Poor power supply can lead to poor radio performance especially if the supply voltage is not kept within 
tolerance or is excessively noisy. To help reduce noise a 1uF and 8.2pF capacitor are recommended to be 
placed as near to pin1 on the PCB as possible. If using a switching regulator for your power supply, switching 
frequencies above 500kHz are preferred. Power supply ripple should be limited to a maximum 250mV peak to 
peak.
Note – For designs using the programmable modules an additional 10uF decoupling cap is recommended near 
pin 1 of the module. The nearest proximity to pin 1 of the 3 caps should be in the following order: 8.2pf, 1uF 
followed by 10uF.
EM250 Pin Number XBee Pin Number
Other Usage
13 (Reset)
5*
Connected to pin 8 on 2x5 SIF header.
19 (GPIO 11)
16*
20 (GPIO 12)
12*
21 (GPIO 0)
15
22 (GPIO 1)
XBee
Tied to ground (module identification)
XBee-PRO (S2)
Low-asserting shutdown line for output power compensation circuitry. 
XBee-PRO (S2B)
Used to communicate with Temp Sensor and control Shutdown for low power mode.
24 (GPIO 2)
XBee
Not connected. Configured as output low.
XBee-PRO (S2)
Powers the output power compensation circuitry.
XBee-PRO (S2B)
Used to communicate with Temp Sensor and control Shutdown for low power mode.
25 (GPIO 3)
13
26 (GPIO 4 / ADC 0)
20
Connected to pin 9 on 2x5 SIF header.
27 (GPIO 5 / ADC 1)
19
Connected to pin 10 on 2x5 SIF header.
29 (GPIO 6 /ADC 2)
18
30 (GPIO 7 / ADC 3
17
31 (GPIO 8)
4
32 (GPIO 9)
2*
33 (GPIO 10)
3* 
34 (SIF_CLK)
Connected to pin 6 on 2x5 SIF header.
35 (SIF_MISO)
Connected to pin 2 on 2x5 SIF header.
36 (SIF_MOSI)
Connected to pin 4 on 2x5 SIF header.
37 (SIF_LOAD)
Connected to pin 7 on 2x5 SIF header.
40 (GPIO 16)
7
41 (GPIO 15)
6
42 (GPIO 14)
9
43 (GPIO 13)
11