XBeePins
Configuring an XBee for I/O samples can be a frustrating experience. First you have to look in the Digi command reference table to find out what pins support Digital or Analog, then determine the location of the physical pin, and finally determine the API method to call to get the value. This guide attempts to simply the process.
The following image shows the physical layout of pins 1 through 20 of an XBee. Although this is a series 2 XBee, the pin layout is identical to series 1 (805.15.4), both Pro and standard.
If you are using the XBee Explorer, remember it has two extra pins, GND and 5V, as shown
| Pin # | AT Command | Description | Default Configuration | Supported Configurations (Value) | Analog I/O Method | Digital I/O Method |
|---|---|---|---|---|---|---|
| 1 | n/a | Power Supply | n/a | n/a | n/a | |
| 2 | n/a | UART Data Out | n/a | n/a | n/a | |
| 3 | n/a | UART Data In | n/a | n/a | n/a | |
| 4 | n/a | Digital Output 8 (not supported as of 2/28/09) | n/a | n/a | n/a | |
| 5 | n/a | Module Reset (reset pulse must be at least 200 ns) | n/a | n/a | n/a | |
| 6 | P0 | PWM Output 0 / RX Signal Strength Indicator | RSSI_PWM | DISABLED (0x0), RSSI_PWM (0x1), PWM_OUTPUT (0x2) | n/a | n/a |
| 7 | P1 | PWM Output 1 | DISABLED | DISABLED (0x0), RSSI_PWM (0x1), PWM_OUTPUT (0x2) | n/a | n/a |
| 8 | n/a | Do not connect | n/a | n/a | n/a | |
| 9 | D8 | DTR / Pin Sleep Control Line or Digital Input 8 | DISABLED | DISABLED (0x0), DIGITAL_INPUT (0x3) | n/a | isD8On() |
| 10 | n/a | Ground | n/a | n/a | n/a | |
| 11 | D4 | Analog Input 4 or Digital I/O 4 | DISABLED | DISABLED (0x0), ANALOG_INPUT (0x2), DIGITAL_INPUT (0x3), DIGITAL_OUTPUT_LOW (0x4), DIGITAL_OUTPUT_HIGH (0x5) | getAnalog4() | isD4On() |
| 12 | D7 | Clear-to-Send Flow Control or Digital I/O 7 | CTS_FLOW_CTRL | DISABLED (0x0), CTS_FLOW_CTRL (0x1), DIGITAL_INPUT (0x3), DIGITAL_OUTPUT_LOW (0x4), DIGITAL_OUTPUT_HIGH (0x5) | n/a | isD7On() |
| 13 | n/a | Module Status Indicator | n/a | n/a | n/a | |
| 14 | n/a | Voltage Reference for A/D Inputs | n/a | n/a | n/a | |
| 15 | D5 | Associated Indicator, Analog Input 5 or Digital I/O 5 | ASSOC_LED | DISABLED (0x0), ASSOC_LED (0x1), ANALOG_INPUT (0x2), DIGITAL_INPUT (0x3), DIGITAL_OUTPUT_LOW (0x4), DIGITAL_OUTPUT_HIGH (0x5) | getAnalog5() | isD5On() |
| 16 | D6 | Request-to-Send Flow Control, Analog Input 6 or Digital I/O 6 | DISABLED | DISABLED (0x0), RTS_FLOW_CTRL (0x1), DIGITAL_INPUT (0x3), DIGITAL_OUTPUT_LOW (0x4), DIGITAL_OUTPUT_HIGH (0x5) | n/a | isD6On() |
| 17 | D3 | Analog Input 3 or Digital I/O 3 | DISABLED | DISABLED (0x0), ANALOG_INPUT (0x2), DIGITAL_INPUT (0x3), DIGITAL_OUTPUT_LOW (0x4), DIGITAL_OUTPUT_HIGH (0x5) | getAnalog3() | isD3On() |
| 18 | D2 | Analog Input 2 or Digital I/O 2 | DISABLED | DISABLED (0x0), ANALOG_INPUT (0x2), DIGITAL_INPUT (0x3), DIGITAL_OUTPUT_LOW (0x4), DIGITAL_OUTPUT_HIGH (0x5) | getAnalog2() | isD2On() |
| 19 | D1 | Analog Input 1 or Digital I/O 1 | DISABLED | DISABLED (0x0), ANALOG_INPUT (0x2), DIGITAL_INPUT (0x3), DIGITAL_OUTPUT_LOW (0x4), DIGITAL_OUTPUT_HIGH (0x5) | getAnalog1() | isD1On() |
| 20 | D0 | Analog Input 0 or Digital I/O 0 | DISABLED | DISABLED (0x0), ANALOG_INPUT (0x2), DIGITAL_INPUT (0x3), DIGITAL_OUTPUT_LOW (0x4), DIGITAL_OUTPUT_HIGH (0x5) | getAnalog0() | isD0On() |
Example: You want to read an analog sensor on a remote XBee end device. Look in the table for an available pin that supports ANALOG_INPUT; let's use 11. In the table we can see that the AT Command for pin 11 is D4 and the ANALOG_INPUT parameter value is 0x2. Now plug your end device into your computer and open X-CTU. Select enable API mode and use escape characters. On the Modem Configuration tab and click "Read". Find D4 in and set to "2 - ADC". Now enable I/O samples by setting IR to "1388" (every five seconds) and click "Write" to save the configuration. Now connect the XBee coordinator to your PC and start receiving the samples with the getAnalog4() method in the IoSample.java class.
| Pin # | AT Command | Description | Default Configuration | Supported Configurations (Value) | Analog I/O Method | Digital I/O Method |
|---|---|---|---|---|---|---|
| 1 | n/a | Power Supply | n/a | n/a | n/a | |
| 2 | n/a | UART Data Out | n/a | n/a | n/a | |
| 3 | n/a | UART Data In | n/a | n/a | n/a | |
| 4 | P2 | Digital I/O 12 | UNMONITORED_INPUT | UNMONITORED_INPUT (0x0), DIGITAL_INPUT (0x3), DIGITAL_OUTPUT_LOW (0x4), DIGITAL_OUTPUT_HIGH (0x5) | n/a | isD2On() |
| 5 | n/a | Module Reset (reset pulse must be at least 200 ns) | n/a | n/a | n/a | |
| 6 | P0 | PWM Output 0 / RX Signal Strength Indicator / Digital IO | RSSI_PWM | DISABLED (0x0), RSSI_PWM (0x1), DIGITAL_INPUT (0x3), DIGITAL_OUTPUT_LOW (0x4), DIGITAL_OUTPUT_HIGH (0x5) | n/a | isD10On() |
| 7 | P1 | Digital I/O 11 | UNMONITORED_INPUT | UNMONITORED_INPUT (0x0), DIGITAL_INPUT (0x3), DIGITAL_OUTPUT_LOW (0x4), DIGITAL_OUTPUT_HIGH (0x5) | n/a | isD1On() |
| 8 | n/a | Do not connect | n/a | n/a | n/a | |
| 9 | n/a | DTR / Pin Sleep Control Line | n/a | n/a | n/a | |
| 10 | n/a | Ground | n/a | n/a | n/a | |
| 11 | D4 | Digital I/O 4 | DISABLED | DISABLED (0x0), DIGITAL_INPUT (0x3), DIGITAL_OUTPUT_LOW (0x4), DIGITAL_OUTPUT_HIGH (0x5) | n/a | isD4On() |
| 12 | D7 | Clear-to-Send Flow Control or Digital I/O 7 | CTS_FLOW_CTRL | DISABLED (0x0), CTS_FLOW_CTRL (0x1), DIGITAL_INPUT (0x3), DIGITAL_OUTPUT_LOW (0x4), DIGITAL_OUTPUT_HIGH (0x5), RS485_TX_LOW (0x6), RS485_TX_HIGH (0x7) | n/a | isD7On() |
| 13 | n/a | Module Status Indicator | n/a | n/a | n/a | |
| 14 | n/a | Not used on this module. For compatibility with other XBee modules, we recommend connecting this pin to a voltage reference if Analog sampling is desired. Otherwise, connect to GND | n/a | n/a | n/a | |
| 15 | D5 | Associated Indicator, Digital I/O 5 | ASSOC_LED | DISABLED (0x0), ASSOC_LED (0x1), DIGITAL_INPUT (0x3), DIGITAL_OUTPUT_LOW (0x4), DIGITAL_OUTPUT_HIGH (0x5) | n/a | isD5On() |
| 16 | D6 | Request-to-Send Flow Control, Digital I/O 6 | DISABLED | DISABLED (0x0), RTS_FLOW_CTRL (0x1), DIGITAL_INPUT (0x3), DIGITAL_OUTPUT_LOW (0x4), DIGITAL_OUTPUT_HIGH (0x5) | n/a | isD6On() |
| 17 | D3 | Analog Input 3 or Digital I/O 3 | DISABLED | DISABLED (0x0), ANALOG_INPUT (0x2), DIGITAL_INPUT (0x3), DIGITAL_OUTPUT_LOW (0x4), DIGITAL_OUTPUT_HIGH (0x5) | getAnalog3() | isD3On() |
| 18 | D2 | Analog Input 2 or Digital I/O 2 | DISABLED | DISABLED (0x0), ANALOG_INPUT (0x2), DIGITAL_INPUT (0x3), DIGITAL_OUTPUT_LOW (0x4), DIGITAL_OUTPUT_HIGH (0x5) | getAnalog2() | isD2On() |
| 19 | D1 | Analog Input 1 or Digital I/O 1 | DISABLED | DISABLED (0x0), ANALOG_INPUT (0x2), DIGITAL_INPUT (0x3), DIGITAL_OUTPUT_LOW (0x4), DIGITAL_OUTPUT_HIGH (0x5) | getAnalog1() | isD1On() |
| 20 | D0 | Analog Input 0, Digital IO 0, or Commissioning Button | NODE_ID_ENABLED | DISABLED (0x0), NODE_ID_ENABLED (0x1), ANALOG_INPUT (0x2), DIGITAL_INPUT (0x3), DIGITAL_OUTPUT_LOW (0x4), DIGITAL_OUTPUT_HIGH (0x5) | getAnalog0() | isD0On() |
Example: You want to read an digital sensor on a remote XBee end device. Look in the table for an available pin that supports DIGITAL_INPUT; let's use pin 20. In the table we can see that the AT Command for pin 20 is D0 and the DIGITAL_INPUT parameter value is 0x3. Now plug your end device into your computer and open X-CTU. Select enable API mode and use escape characters. On the Modem Configuration tab and click "Read". Find D0 in and set to "3 - DIGITAL INPUT". Now enable I/O samples by setting IR to "1388" (every five seconds) and click "Write" to save the configuration. Now connect the XBee coordinator to your PC and start receiving the samples with the isD0On() method in the ZNetRxIoSampleResponse.java class.
Note: Both these tables were generated by the printAll method in XBeePin.java You may find this class useful for programmatically determining the capabilities of XBee pins.