Wireless/Zigbee for PIC Micros
April 9, 2013
Back in 2009, my professional work involved leading the firmware project of a low power wireless network of sensors collecting temperature and humidity data. Wireless gateways accumulated the information and sent to a data center over the internet. During that project, I fancied my own Zigbee network for my robots and setting up a network of home monitoring sensors. I eventually bought some Microchip MRF24J40MA modules (which is a completely different platform than my professional work). Unfortunately, the modules had been siting idle for more than 3 years and until very recently, I didn't get a chance to play with them.
Microchip has a great library called Miwi which provides out of the box Zigbee like infrastructure based and P2P protocols. There are plenty of demo boards available as well. However, to fit wireless into projects where space is a luxury, you need to get your hands dirty.
I prefer building my own platforms from the scratch rather than using ready solutions like the microchip demo boards or even the Arduino and Zigbee shields. While Arduino and its sheilds are excellent kits for beginners, I feel I have a different taste. Arduino + Zigbee shields are insanely expensive as well. For example, a set Arduino + Zigbee shields will cost £40 or more while PIC + its radio modules are less than £7. So you can easily have a whole network of PICs with the price of one bulky Arduino Zigbee :). I'm happy with any low level programming challenge the PIC solution might through at me (In fact, that's what I really enjoy doing).
I'm using the PIC18F26K20 for the network. With 64KB ROM, 4K RAM, 16 mips/64 MHz and XLP, it has been adequate for my hobbits works for some years. Here's how my prototypes look like:
Sending data to the Zena network analyzer.
Sending and receiving tests with two sets of modules.
So my Zigbee network is ready to be plugged in (to my next projects). The assembled version of these prototype boards will look very different. I'll introduce the PCB version soon.
Sharing my original post from here: http://kontroller.blogspot.co.uk/2013/04/wirelesszigbee-for-pic-micros.html