Digi XBee S2C 802.15.4 User Manual Download

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Operation

Sleep support

XBee/XBee-PRO S2C 802.15.4 RF Module User Guide

I/O line passing details

The same message is received for both I/O sampling and for I/O line passing. But I/O line passing only
occurs if

matches the short or long address of the sending node or if

is 0xFFFF to match a

sample from any node. The default value of

is 0xFFFFFFFF, which prevents I/O line passing from

occurring on the node because no node has that address. Additionally, the receiving device must have
a matching value for output. For example, if an ADC0 sample is received, then

must be configured

with 2 for PWM output. Otherwise, the analog signal will not be reflected with a matching PWM signal.
Likewise, if the sample indicates that D2 is high, but

is not set to 4 or 5 on the receiving device,

then the D2 pin will not be affected by I/O line passing.

When a digital output pin is set to something different than its configured value, that pin may return to
its configured value after the time specified for the corresponding timer.

specifies how long D0 will

hold its non-configured value and

specifies how long D1 will hold its non-configured value. A value of

0xFF indicates that a pin holds the value of the input of the corresponding device indefinitely and a
value less than 0xFF specifies how many tenth second units the pin holds the non-configured value.

For PWM outputs, PT timer applies to both PWM0 and PWM1. A value of 0xFF allows the PWM pin to
output a duty cycle reflective of the analog input indefinitely and a smaller value indicates how many
10th second units before PWM output reverts to the duty cycle specified by

Output control

The

(Digital Output Level) command controls the output levels of D0 through D7 that are configured

as output pins (either 4 or 5). These values override the configured output levels of the pins until they
are changed again (the pins do not automatically revert to their configured values after a timeout.)
You can use the

command to trigger a sample on change detect.

Sleep support

Set

SO (Sleep Options)

bit 1 to suppress automatic wake-up sampling.

When a device wakes, it always performs a sample based on any active ADC or DIO lines. This allows
sampling based on the sleep cycle whether it be Cyclic Sleep (

= 4 or 5) or Pin Sleep (

= 1). Set

the

IR (Sample Rate)

parameter to gather more samples when awake.

For Cyclic Sleep modes: If the

parameter is set, the device stays awake until the

IT (Samples before

TX)

parameter is met. The device stays awake for

ST (Time before Sleep)

Sleep modes

Sleep modes enable the device to enter states of low-power consumption when not in use. In order to
enter Sleep mode, one of the following conditions must be met (in addition to the device having a non-
zero

parameter value):

SLEEP_RQ/DTR (pin 9 on through-hole devices, pin 10 on surface-mount devices) is asserted
and the device is in a pin sleep mode (

= 1, or 5)

The device is idle (no data transmission or reception) for the amount of time defined by the

(Time before Sleep) parameter.

Note

is only active when

= 4 or 5.

The following table shows the sleep mode configurations.