Digi International Inc XBEEPRO2 Manual Do Utilizador
XBee®/XBee‐PRO® ZB RF Modules
© 2011 Digi International, Inc.
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•Broadcast transmissions can support 8 bytes more than unicast transmissions.
•If source routing is used, the 16-bit addresses in the source route are inserted into the RF payload space. For
•If source routing is used, the 16-bit addresses in the source route are inserted into the RF payload space. For
example, if NP returns 84 bytes, and a source route must traverse 3 intermediate hops (3 16-bit addresses),
the total number of bytes that can be sent in one RF packet is 78.
•Enabling APS encryption (API tx option bit set) will reduce the number of payload bytes by 4.
•Enabling APS encryption (API tx option bit set) will reduce the number of payload bytes by 4.
Throughput
Throughput in a ZigBee network can vary by a number of variables, including: number of hops, encryption enabled/
disabled, sleeping end devices, failures/route discoveries. Our empirical testing showed the following throughput
performance in a robust operating environment (low interference).
disabled, sleeping end devices, failures/route discoveries. Our empirical testing showed the following throughput
performance in a robust operating environment (low interference).
Data Throughput*
RR = router to router,
RE = router to end device (non-sleeping),
ER = end device (non-sleeping) to router,
SD = security disabled,
SE = security enabled.
4 hops = 5 nodes total, 3 intermediate router nodes
* Data throughput measurements were made setting the serial interface rate to 115200 bps, and measuring the
time to send 100,000 bytes from source to destination. During the test, no route discoveries or failures occurred.
time to send 100,000 bytes from source to destination. During the test, no route discoveries or failures occurred.
ZDO Transmissions
ZigBee defines a ZigBee Device Objects layer (ZDO) that can provide device and service discovery and network
management capabilities. This layer is described below.
management capabilities. This layer is described below.
ZigBee Device Objects (ZDO)
The ZigBee Device Objects (ZDO) is supported to some extent on all ZigBee devices. The ZDO is an endpoint
that implements services described in the ZigBee Device Profile in the ZigBee specification. Each service has an
assigned cluster ID, and most service requests have an associated response. The following table describes some
common ZDO services.
that implements services described in the ZigBee Device Profile in the ZigBee specification. Each service has an
assigned cluster ID, and most service requests have an associated response. The following table describes some
common ZDO services.
Configuration
Data Throughput
1 hop, RR, SD
35kbps
1 hop, RR, SE
19kbps
1 hop, RE, SD
25kbps
1 hop, RE, SE
16kbps
1 hop, ER, SD
21kbps
1 hop, ER, SE
16kbps
4 hops, RR, SD 10kbps
4 hops, RR, SE 5kbps
Cluster Name Cluster ID Description
Network Address
Request
0x0000
Request a 16-bit address of the
radio with a matching 64-bit
address (required parameter).
Active Endpoints
Request
0x0005
Request a list of endpoints from a
remote device.