Let's compare the two radios, along with ZigBee vs. TinyOS. CC2420: * Hardware supported 802.15.4 compatibility - although it takes some amount of software support to make it 100% compatible.
* Not "ZigBee" without software support. Implementation of the ZigBee protocol is what makes something ZigBee. TinyOS baseline does not implement the ZigBee protocol, but it can. Here's a comparison: ZigBee specs make for high power networks (even though it's marketed as "low power"), geared for building applications that can support dedicated power supplies for coordinator and router nodes. End nodes can be very low power and made using very inexpensive hardware because they aren't intelligent. "ZigBee" is only a marketing term for an industrial-driven wireless protocol that is not TinyOS. TinyOS philosophy is geared toward actual low power networks - where the equivalent of ZigBee 'end nodes' are allowed to do processing in terms of routing, which improves the energy consumption of the network as a whole. TinyOS networks can survive on batteries for a number of years. ZigBee routers/coordinators can survive on D-cell lithium batteries for ~2 weeks. ZigBee == indoors only. TinyOS == indoors and outdoors. You can make a network that acts like a ZigBee network in TinyOS, but you could also make a network that is more efficient than a ZigBee network in TinyOS. Depending on the target application, claiming to be "ZigBee certified" may not be a good thing. Continuing on... * Direct Sequence Spread Spectrum (DSSS) modulation * 2400 - 2482 MHz * Packet radio - sends and receives entire packets of information, does automatic reception, CRC's, acks, AES-128, etc. CC1000: * Can implement the 802.15.4 specified headers through software * 300 - 1000 MHz * FSK modulation * Byte radio - sends and receives bytes. Software is responsible for generating and detecting packet preambles, as well as everything else. -David -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Benjamin Madore Sent: Tuesday, April 03, 2007 12:32 PM To: nikhil Cc: [email protected] Subject: RE: RE: [Tinyos-help] telosb and mica2 On Tue, April 3, 2007 2:37 pm, nikhil said: > Also the network communication specification followed by Telosb and Mica is > different. Telosb uses Zigbee while mica does not use zigbee. Only > difference in frequency is not the necessary reason for them not > communicating with each other. > Please correct me if I am wrong. > > - Nikhil Shah I'm not sure if you are referring to the packet type or the encoding, but you are basically correct. If I understand the specifications correctly, the two radios work in different ways. They transmit using different strategies, different radio encodings, and different error correction. Even if they were the same frequency, it would be unlikely that they could talk to each other. The CC2420(Zigbee) chip is also more "intelligent" -- it does some of the processing itself that the CC1000 requires the CPU to do. The Mica uses a different radio yet from the Mica2 and the MicaZ/Telosb/etc. and is completely incompatible with all the others, even at the same frequency. I'm not sure there is a clear table of these differences out there. There ought to be, there are many types of motes on the market, and there should be a quick reference. Does anyone still update a TinyOS wiki? -- The difference between the right word and the almost right word is really a large matter- it's the difference between a lightning bug and the lightning. -Twain _______________________________________________ Tinyos-help mailing list [email protected] https://mail.millennium.berkeley.edu/cgi-bin/mailman/listinfo/tinyos-help _______________________________________________ Tinyos-help mailing list [email protected] https://mail.millennium.berkeley.edu/cgi-bin/mailman/listinfo/tinyos-help
