XBIB-R Digi International/Maxstream, XBIB-R Datasheet - Page 17

• Manufacturer Part Number: XBIB-R
• Description: BOARD RS232 ZIGBEE MOD PRO
• Manufacturer: Digi International/Maxstream

Specifications of XBIB-R

• Design Resources: XBIB-R Schematic
• Accessory Type: Interface Board
• For Use With/related Products: XBee and XBee Pro Radios
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

XBee/XBee‐PRO™ OEM RF Modules ‐ 802.15.4 ‐ v1.xAx [2007.05.031]
End Device Power-up
2. Check A2 parameter - Reassign_Channel Flag (bit 1)
3. Start Coordinator
4. Coordinator Modifications
End Device power-up is governed by the A1 (End Device Association) command. On power-up, the
End Device undergoes the following sequence of events:
1. Check A1 parameter - AutoAssociate Bit
2. Discover Coordinator (if Auto-Associate Bit Set)
© 2007 MaxStream, Inc.
Set (bit 1 = 1) - The Coordinator issues an Energy Scan. The Energy Scan selects one channel
and scans for energy on that channel. The duration of the scan is specified by the SD (Scan
Duration) parameter. Once the scan is completed on a channel, the Energy Scan selects the
next channel and begins a new scan on that channel. This process continues until all channels
have been scanned.
When the Energy Scan is complete, the results include the maximal energy values detected on
each channel. This list is used to determine a channel where the least energy was detected. If
an Active Scan was performed (Reassign_PANID Flag set), the channels used by the detected
PANs are eliminated as possible channels. Thus, the results of the Energy Scan and the Active
Scan (if performed) are used to find the best channel (channel with the least energy that is not
used by any detected PAN). Once the best channel has been selected, the CH (Channel) param-
eter value is updated to that channel.
Not Set (bit 1 = 0) - The Coordinator retains its CH setting. An Energy Scan is not performed.
The Coordinator starts on the specified channel (CH parameter) and PAN ID (ID parameter).
Note, these may be selected in steps 1 and/or 2 above. The Coordinator will only allow End
Devices to associate to it if the A2 parameter “AllowAssociation” flag is set. Once the Coordina-
tor has successfully started, the Associate LED will blink 1 time per second. (The LED is solid if
the Coordinator has not started.)
Once a Coordinator has started:
Modifying the A2 (Reassign_Channel or Reassign_PANID bits), ID, CH or MY parameters will
cause the Coordinator’s MAC to reset (The Coordinator RF module (including volatile RAM) is
not reset). Changing the A2 AllowAssociation bit will not reset the Coordinator’s MAC. In a non-
beaconing system, End Devices that associated to the Coordinator prior to a MAC reset will have
knowledge of the new settings on the Coordinator. Thus, if the Coordinator were to change its
ID, CH or MY settings, the End Devices would no longer be able to communicate with the non-
beacon Coordinator. Once a Coordinator has started, the ID, CH, MY or A2 (Reassign_Channel
or Reassign_PANID bits) should not be changed.
Set (bit 2 = 1) - End Device will attempt to associate to a Coordinator. (refer to steps 2-3).
Not Set (bit 2 = 0) - End Device will not attempt to associate to a Coordinator. The End Device
will operate as specified by its ID, CH and MY parameters. Association is considered complete
and the Associate LED will blink quickly (5 times per second). When the AutoAssociate bit is not
set, the remaining steps (2-3) do not apply.
The End Device issues an Active Scan. The Active Scan selects one channel and transmits a
BeaconRequest command to the broadcast address (0xFFFF) and broadcast PAN ID (0xFFFF). It
then listens on that channel for beacons from any Coordinator operating on that channel. The
listen time on each channel is determined by the SD parameter.
Once the time expires on that channel, the Active Scan selects another channel and again
transmits the BeaconRequest command as before. This process continues until all channels
have been scanned, or until 5 PANs have been discovered. When the Active Scan is complete,
the results include a list of PAN IDs and Channels that are being used by detected PANs.
Chapter 2 ‐ RF Module Operation
17