Communication protocol for use with a data acquisition and retrieval system with handheld user interface

Abstract

A packet-based communication protocol for communicating messages between computing devices over a communication link therebetween (such as between a communication server and hand-held data acquisition device over a wireless link therebetween), each message comprising a plurality of equal length information packets. A first information packet in each message is constructed with a first format including a long header and a data segment. All information packets subsequent to the first information packet in each message are constructed with a second format including a short header and a data segment. The data segments from the plurality of information packets within each message form a single data set related to a single matter. The use of the short header in the second format information packets maximizes the amount of information contained in such information packets and thus provides for improved information throughput.

2 . A communication protocol comprising: 
 multiple communications messages transmitted between a first computer and a second computer, each message comprising a plurality of information packets, each of which being equal in length, wherein a first information packet in each message is constructed with a first format including a long header and a data segment, and wherein all information packets subsequent to said first information packet in each message are constructed with a second format including a short header and a data segment, the data segments from said plurality of information packets within each message forming a single data set related to a single matter.    
     
     
         3 . The communications protocol of  claim 2 , wherein the long header includes a command field identifying a process to be performed upon the corresponding data segment, a user ID for identifying a user logged into the first computer and a message total field identifying a total length of the single data set corresponding to a current message within the present information packet and all subsequent information packets associated with said current message.  
     
     
         4 . The communications protocol of  claim 2 , wherein the short header includes a command field for identifying a process to be performed upon the corresponding data segment, and a positioning packet identifying a position of a corresponding information packet within a current message.  
     
     
         5 . The communications protocol of  claim 2 , wherein the data segments within information packets having the second format are longer than the data segments within information packets having the first format.  
     
     
         6 . The communications protocol of  claim 2 , further comprising: 
 means for reading a current data set from work space memory in a handheld user interface;    means for determining a length of a message corresponding to said current data set and for determining a user ID of the user logged into said handheld user interface;    means for constructing said first information packet within a transmit buffer of the handheld user interface, said first information packet including said long head and a data segment derived from at least a portion of said current data set.    
     
     
         7 . The communications protocol of  claim 6 , further comprising: 
 means, within the handheld user interface for transmitting a current information packet within the transmit buffer and clearing said transmit buffer; and    means for constructing at least one information packet subsequent to said first information packet including said short header along with a next data segment derived from said current data set, when said current data set is longer than said data segment of said first information packet.    
     
     
         8 . The communications protocol of  claim 2 , further comprising: 
 a receiver/transmitter, within a communications/command server, for receiving and transmitting said information packets from and to at least one handheld user interface;    a temporary buffer for storing each information packet from each communication channel, each communication channel corresponding to a unique handheld user interface; and    an input buffer for storing received information packets while a CPU converts said received information packets from said first and second formats to a message list format.    
     
     
         9 . The communications protocol of  claim 8 , wherein said message list format includes command information related to messages received from said at least one handheld user interface, said command information including a device number uniquely identifying the handheld user interface transmitting a given message, a command to be processed in accordance with the given message, a packet number identifying a position of the current information packet within the given message, a destination user ID identifying a user to which said given message is addressed, a message total length identifying a total length of said single data set for the given message, a message length identifying a portion of said given message currently received, and a message pointer into a message buffer to a location of said given message.