I recommend the ZigBee protocol only when a design requires interoperability with other ZigBee devices, or when someone wants a ZigBee certification. For proprietary designs or basic wireless communications, modules that operate to the IEEE 802.15.4 standard will do a nice job without the software overhead ZigBee requires.
I was once very interested in those TI 802.15.4 SoCs, but those currently in production use an 8051 core and to do anything useful with them requires a heafy investment in development tools (eg IAR which costs 2-3k$). No thank you, ARM for me please.
Fifty-six-year-old Pasquale Russo has been doing metalwork for more than 30 years in a tiny southern Italy village. Many craftsmen like him brought with them fabrication skills when they came from the Old World to America.
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