Specifications

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the main microcontroller through the ZigBee method, it too must have some
basic requirements, which are also listed below in Table 9.
Main Microcontroller Wireless
Module Requirements
Secondary Microcontroller Wireless
Module Requirements
Low power consumption
Low power consumption
Easy integration to the system
Easy integration to the system
Small size and surface mountable
Small size and surface mountable
Have security protocols
Low current consumption
Wi-Fi® certified
Different modes for different uses
Low current consumption
Handles low data rates
Different modes for different uses
Excellent range
Excellent range
Table 9 Main and Secondary microcontroller wireless module requirements
Microchip‟s® Wireless Design Center (http://www.microchip.com/wireless) was
an excellent resource when searching for wireless solutions for our project. The
MRF24WB0 Wi-Fi module product family meets the requirements for connecting
the MCU to the internet for our project. The MRF24WB0MA has an integrated
PCB antenna, while the MRF24WB0MB has an external antenna option with an
ultra miniature coaxial connector for extended range. For the scope and
requirements of this project, having the integrated PCB antenna instead of an
external antenna will make for a smooth implementation into the embedded
system. The MRF24J40 ZigBee module product family meets the secondary
microcontroller requirements for communication of the different devices in our
system. Both MRF24J40MA and MRF24J40MB modules have an integrated
PCB antenna, the only difference is that MRF24J40MA has a 400 ft range, while
the MRF24J40MB has a range of 4000 ft. Have that extended range makes
MRF24J40MB a great choice for our ZigBee wireless module. In the sections
below, are detail specifications about each of the two wireless chips from
Microchip®.
2.7 Smart Phone Application
2.7.1 Remote Access
The purpose of having remote access in the Efficient HVAC Control and
Feedback System is to provide the end user instant feedback and control of the
system. This is a key feature of the overall system. This is important because
the number of people with internet ready mobile devices is constantly growing.