William Wong
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ED Online ID #17789 |
December 11, 2007
AeroComm’s compact ZB2430 module (25.4mm by 34.3mm) provides developers with a quick, reliable way of utilizing ZigBee. It is a complete system that can be used without having to go through FCC approval since you don’t modify the 2.4GHz RF or 802.15.4 protocol stacks.
The chip has 128Kbytes of flash although a sizable chunk is dedicated to the protocol stack and its support. The module can also adjust its transmit output power allowing finer control when making range and power consumption tradeoffs. Versions of the module are available with an on-board antenna and with an external antenna.
The SDK-ZB2430 development kit includes a USB-based coordinator (Fig. 1) and four nodes (Fig. 2). The latter can operate off a 9-V battery (not included) or an external power supply (included).
The coordinator and router nodes all use the same ZB2430 module. The module can be set up as an end node as well. The system supports the various ZigBee topologies including a mesh network where routers provide links throughout the network.
The coordinator is used primarily as a diagnostic and management tool. It provides a way to access the network and can be used as a gateway between a PC application, like a configuration program (Fig. 3) included with the system, and the network.
The modules are controlled using an AT-style command set via a serial interface. Likewise, commands can be sent across the network. The commands can read and write the digital IO and read the ADC and temperature sensor on the module. There is also a collection of network management commands as well.
An API Mode packet level communication system is built on top of this, supporting point-to-point operation as well as broadcasting. This is typically used when a host processor is connected to the module.
Out Of The Box
The modules are all preprogrammed and work with the management applications provided with the system. This includes a basic (only with respect to its interface) spectrum analyzer and a configuration program. The latter provides diagnostic and network management capabilities as well. It is designed to work with a pair of nodes, usually the coordinator and another node connected via the serial port.
The nodes were set up for auto-discovery so everything came up quickly. It took more time to read the various manuals than to get the system going with the configuration program.
While getting started was easy, the follow-through is more limited, since you're ready to start hooking together a system. This means you need something to hook the nodes to. The schematics for the boards are included but there is no header access to the digital and analog ports. Likewise, there are no sample applications for the API Mode.
Moving to the next level isn't challenging because both the API Mode and access to the IO ports are relatively simple. A few more coding examples for something like a data acquisition system would be a handy addition.
Overall, the hardware was solid and the included software worked without a hitch. A little more would be nice on the instructional documentation side although individual coverage of the modules and applications was verbose and useful.
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