Start • XBee ZigBee Module • Ethernet in ZigBee • More to Come • Sources and PDF

MORE TO COME

Unfortunately, I can’t show you MaxStream’s beta firmware because it isn’t available as I write this. I can tell you that the new XBee and XBee-Pro beta firmware will allow you to exploit the free analog and digital I/O pins of the XBee’s M9S08GT60 microcontroller. 

I recently noticed that the XBee datasheets identified various analog-to-digital inputs and digital I/O pins within the XBee pinout. Because these features were called out, I figured I could access them and eliminate having to include a microcontroller to collect data for the XBee module. After reading and rereading the XBee datasheets and examining the XBee OEM application document, I couldn’t find anything that I could use to write the code to access the XBee analog and digital I/O pins. An online chat session with Maxstream engineering revealed that I wasn’t losing it. I learned that the firmware for manipulating the XBee analog and digital I/O pins was in the works and had not been released.

Without the ability to program an XBee module for stand-alone duty, I resorted to the resources of the XBee development kit. I used the null modem adapter that came with the kit to attach the RS-232-equipped XBee development pod to my ZigBee bridge PCB’s serial port. In lieu of a microcontroller/XBee module lashup at the remote end of the PAN, I used the kit’s USB-attached XBee development pod and my laptop to simulate the remote data-collecting ZigBee node. The XBee development pods contain integral RS-232 and USB ports, power supply circuitry, and a socket for the XBee module. If you want to decide whether or not to get serious with Maxstream’s XBee modules, you may want to consider procuring the XBee development kit. It will save you the hassle of building up special XBee evaluation and prototype hardware.

It costs a minimum of $3,500 to join the ZigBee Alliance. Ouch! For a tenth of that, you can get an XBee development kit and discover that Maxstream’s XBee modules aren’t expensive or complicated. They’re full-blown ZigBee, and they’re embedded.