31-03-2012, 12:39 PM
LITRATURE SURVEY
Interfacing Keypad with 8051.doc (Size: 233 KB / Downloads: 39)
How does the system work?
The waiter takes the orders on remote locations with the WaiterMate Hand-terminal. These orders are received by the transceiver (the Homebase). The Homebase confirms the order to the WaiterMate! The Homebase sends the orders to the central PC or Cash Register. The orders are split automatically to the different ticket printers (Bar, Kitchen, others.)
The latest revolution in the restaurant business isn't taking place in Paris or London or even Berlin for that matter. It's happening in an odd location -- a non-descript industrial building on the outskirts of Nuremberg in Bavaria. Michael Mack, who got his start operating a profitable iron foundry in the city, has reinvented the way guests are served food and drinks and infused the culinary world with a bit of the Jetsons.
Expansion of the system
To cover large areas, WaiterMate can easily be expanded by adding extra Slave Homebases or wireless Relay Stations. Up to 48 hand terminals can communicate with one Homebase.
Why do pantry owners prefer our system
• Easy order processing on remote locations, using radio frequency for wireless ordering.
• No memorising of numbers: no training needed for new employees.
• Less staff required, even during peak-hours.
• On table payment process.
• Increasing table turns.
• Increasing customer satisfaction.
• Maximising the control of the business by the owner.
• Minimising entry errors.
ZIGBEE
Five years ago, the ZigBee short-range wireless communications standard might have been hawked as a magic key that could unlock the wonders of pervasive computing, a dream of a future in which devices and appliances anticipate their users every need. In todays more careful atmosphere, however, its developers are wisely focusing on a smaller, more attainable goal: letting builders and homeowners cheaply install portable light switches, thermostats, and security systems. If ZigBee wins big in this lighting and control space, however, it may well go on to play a major role in product tracking, medical monitoring, and industrial sensor networks.
Interfacing Keypad with 8051
A keypad is an input device with a small array of push buttons labeled with numbers or other symbols, designed to allow rapid entry of characters from a small set, e.g. decimal digits 0-9 or, historically, hexadecimal digits.
Frequency Agility
ZigBee's operation at 2.4GHz is aided by the choice of 16 available channels. The frequency agility function makes using these extra channels easier. When a network is first formed the node seeks a channel with the least noise or traffic. If over time extra traffic appears or noise becomes present the host application can scan for a better channel and move the whole network to the new channel allowing the network to adapt over time to changing RF environments.
Assymetric Link handling
Within a ZigBee network, paths are selected on the quality of RF communication. This quality between nodes is often asymmetric - better in one direction than the other. ZigBee PRO includes Asymmetric Link Handling which uses regular information exchange between nodes to automatically select optimal links greatly improving network performance.
High security operation
ZigBee PRO security is now better than ever; a network wide security key is mandatory and adds further protection for key management and distribution. Energy management is also improved in networks where ZigBee nodes run on batteries where power management is crucial.