Periodic I/O Sampling; Change Detection Sampling; Rssi Pwm - Digi XBee-PRO S2C Zigbee User Manual

Analog and digital I/O lines
Example
0x01
0x0C0C
0x03
0x0408
0x03D0
0x0124

Periodic I/O sampling

Periodic sampling allows a device to take an I/O sample and transmit it to a remote device at a
periodic rate. Use the IR command to set the periodic sample rate.
To disable periodic sampling, set IR to 0.
n
For all other IR values, the firmware samples data when IR milliseconds elapse and the sample
n
data transmits to a remote device.
The DH and DL commands determine the destination address of the I/O samples.
You can set DH and DL to 0 to transmit to the coordinator, or to the 64-bit address of the remote
device (SH and SL).
Only devices with API operating mode enabled send I/O data samples out their serial interface.
Devices that are in Transparent mode (AP = 0) discard the I/O data samples they receive. You must
configure at least one pin as a digital or ADC input to generate sample data.
A device with sleep enabled transmits periodic I/O samples at the IR rate until the ST time expires and
the device can resume sleeping.

Change detection sampling

You can configure devices to transmit a data sample immediately whenever a monitored digital I/O
pin changes state. The IC command is a bitmask used to set which digital I/O lines to monitor for a
state change. If one or more bits in IC is set, the device transmits an I/O sample as soon as it observes
a state change in one of the monitored digital I/O lines. Use DH and DL to specify the 64-bit address to
transmit change detection samples.

RSSI PWM

The XBee/XBee-PRO Zigbee RF Module features an RSSI/PWM pin (TH pin 6/SMT pin 7) that, if enabled,
adjusts the PWM output to indicate the signal strength of the last received packet. Use
(RSSI/PWM0 Configuration)
is set to 1 (and P1 is not set to 1), the RSSI/PWM pin outputs a pulse width modulated signal where
the frequency adjusts based on the received signal strength of the last packet. Otherwise, for all other
P0 settings, use the pin for general purpose IO.
When a data packet is received, if you set P0 to enable the RSSI/PWM feature, the RSSI PWM output
adjusts based on the RSSI of the last packet. The RSSI/PWM output is enabled for a time based on the
RP command. Each time the device receives an RF packet, the RSSI/PWM output adjusts based on the
RSSI of the new packet, and resets the RSSI timer. If the RSSI timer expires, the RSSI/PWM pin drives
low. RP is measured in 100 ms units and defaults to a value of 40 (4 seconds).
XBee/XBee-PRO® S2C Zigbee® RF Module
Sample AT Response
[1 sample set]
[Digital Inputs: DIO 2, 3, 10, 11 enabled]
[Analog Inputs: A/D 0, 1 enabled]
[Digital input states: DIO 3, 10 high, DIO 2, 11 low]
[Analog input ADIO 0= 0x3D0]
[Analog input ADIO 1=0x120]
to enable the RSSI pulse width modulation (PWM) output on the pin. If P0
RSSI PWM
P0
147