Abstract:
A graphical user interface for use in a handheld portable data terminal including a display screen and touch screen for sensing location of user contact. The graphical user interface includes a display sequence that displays multiple virtual regions on the display screen, wherein each virtual region corresponds to an event identifier. An event handler identifies one of the virtual regions that corresponds to the location of user contact sensed by the touch screen, determines a specific event identifier corresponding to the identified virtual region, and processes a predetermined sequence for the specific event identifier. The multiple virtual regions displayed on the display screen by the display routine preferably includes one of a virtual keypad for entering symbols associated with keys of the keypad, at least one scroll bar, at least one rolling key, multiple icons, a menu screen and a graphing screen. The predefined processing sequence associated with a given virtual region of the display screen is initiated by the user by contacting the associated virtual region. The predefined processing sequences may involve one of data entry operations, data communication operations, and code scan operations. The graphical user interface may also include a text input mechanism that enables the user to enter at least a portion of a desired text data, that automatically searches data stored in memory to retrieve text data closest to the portion of desired text data, and displays the retrieved text data on the display screen.

Description:
RELATED CASES 
     This Application is a Continuation of U.S. application Ser. No. 09/241,214 filed Feb. 1, 1999 now U.S. Pat. No. 6,389,477; which is a Continuation of U.S. application Ser. No. 08/196,452 filed Feb. 14, 1994, now U.S. Pat. No. 5,867,688. Each said patent application is assigned to and commonly owned by Metrologic Instruments, Inc. of Blackwood, N.J., and is incorporated herein by reference in its entirety. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates in general to a system for data acquisition and retrieval through the use of a user interface remotely located from the control system. 
     2. Description of the Related Art 
     Today, most commercial businesses require field employees, such as at points of sale, to fill out paper forms with data sets concerning individual customers or products sold/manufactured. These reports are then collected, compiled and assimilated at a central location and filed for future access. Most modern businesses require this information to be continuously updated and that the field personnel be afforded quick access thereto in order to reduce business costs, improve efficiency, increase accuracy, and the like. Heretofore, data sets concerning matters, such as customer or product information, have been primarily compiled through paper forms completed by field personnel and later possibly entered into some form of central database. 
     In the healthcare field, hospitals utilize a significant amount of data retrieval and acquisition, with respect to patient information. All data sets containing patient information (data field) such as patient name (a data set header), date of birth, place of business, address, phone numbers, language, billing account number, social security number, drivers license number, and the like were written on paper forms and maintained in a paper file, and optionally entered by the hospital staff into a common database. Thereafter, the patient information was supplemented with information pertaining to their health condition, such as vital signs, fluid intake, fluid output and the like, which were written on different paper forms by a nurse and later keyed into this common database. Similarly, when patients undergo testing, the test results were manually keyed into the common database and/or written on forms stored in the patient&#39;s paper file. 
     An alternative example lies in the insurance industry in which field claims adjustors travel to the site of an insurance claim and evaluate the damaged property. These adjustors fill out multiple forms identifying the damage and the insured person&#39;s general information. For instance, in an automotive accident the claims adjustor must describe each problem with the insured car, such as dents, scratches, and the like. These forms are later processed manually or keyed into a common database, after which, the claimant ultimately is paid. 
     A substantial amount of data acquisition and retrieval is also utilized in factory environments. During the course of manufacturing various products, floor workers and quality review must complete multiple forms concerning a given production unit. 
     However, every business requiring significant amounts of data acquisition and retrieval in its day-to-day business encounter similar problems. First and foremost, a significant amount of the field operative&#39;s time is required in filling out the corresponding paperwork, in which the potential for user error exists. Also, in systems using paper forms, the information must be ultimately transferred to an electronic database, which provides a second opportunity for user error. Clearly, it would be advantageous to reduce the number of user entries, thereby reducing the likelihood of error. 
     Further, in many markets, field personnel at one location typically require information quickly from another field location. For instance, in a hospital environment, a doctor within the general ward may require immediate information concerning a patient from the radiology department. However, the process under which the information is written down and carried between departments is very slow. Similarly, doctors and nurses require immediate and accurate knowledge of specific procedures to be followed with regard to particular patients. Past systems for maintaining individual patient procedures have proven ineffective. 
     Moreover, one office within a business will typically require information from another office which must be hand carried or which is unavailable after the closing hours of the second office. For instance, hospitals require lab testing results be hand-carried to doctors who may be waiting for such results during the course of surgery. Also, typically doctors require clinical data after the clinics have closed. 
     The need remains in this field for an improved data acquisition and retrieval system to address the problems and drawbacks heretofore experienced. The primary objective of this invention is to meet this need. 
     SUMMARY OF THE INVENTION 
     It is an object of the present invention to provide a data acquisition and retrieval system which allows users immediate real time access to all existing customer/product information. 
     It is an object of the present invention to provide a data acquisition and retrieval system which affords users access to wireless remote data terminals. 
     It is an object of the present invention to minimize the data retrieval time by reducing the necessary information transmitted between handheld units and the corresponding communications server. 
     It is another object of the present invention to minimize the data necessary for transmission by synchronizing operation within each handheld unit and a corresponding communications server, such synchronization including the minimization of header information for each transmission and the transmission of a command case code used directly by the command server to access a designated database. 
     It is another object of the present invention to provide a user interface which minimizes user error. 
     It is another object of the present invention to provide a user interface which utilizes an event driven architecture to allow data entry through a touch pad. 
     It is another object of the present invention to provide an user interface which is easily operated by using a touch pad which presents a scroll bar, rolling keys and icons for data entry. 
     It is another object of the present invention is to provide an user interface which allows for the scanning of bar codes to identify particular customers or products. 
    
    
     These and further objects will become more apparent from the drawings and detailed description hereafter. 
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The objects and features of the invention noted above are explained in more detail with reference to the drawings, in which like reference numerals denote like elements, and in which: 
     FIG. 1 is a block diagram of an overview of a data acquisition and retrieval system according to the present invention; 
     FIG. 2 illustrates a block diagram of a handheld interface according to the present invention; 
     FIG. 3 illustrate exemplary display screens shown on the handheld interface according to the present invention; 
     FIG. 4 illustrates the main processing loop by which the handheld interface monitors and responds to events selected by the user; 
     FIG. 5 illustrates the processing sequence of the handheld interface while displaying a patient information screen; 
     FIG. 6 illustrates the processing sequence of the handheld interface to initiate the patient information screen; 
     FIGS.  7 ( a ) and  7 ( b ) illustrate the processing sequence of the handheld interface while displaying a patient input screen; 
     FIG. 8 illustrates the processing sequence of the handheld interface to initiate the patient input screen; 
     FIG. 9 illustrates the data structure of the packets transmitted between the handheld interface and the communications server; 
     FIG. 10 illustrates the processing sequence undergone by the handheld interface to write data packets to the communications server; 
     FIG. 11 illustrates the processing sequence by which the communication server reads packets transmitted from the handheld interface; 
     FIG. 12 illustrates the processing sequence by which the communication server parses through a short header structure within an incoming packet to build the input buffer; 
     FIG. 13 illustrates the processing sequence by which the communication server parses through a long header structure within an incoming packet to build the input buffer; 
     FIG. 14 illustrates the processing QUEUE sequence to move completed messages to the processing QUEUE; 
     FIG. 15 illustrates the processing sequence by which the communication server generates the processing queue; 
     FIG. 16 illustrates a block diagram of the RAM section of the handheld interface; 
     FIG. 17 illustrates a block diagram of the communications server; 
     FIG. 18 illustrates an alternative data entry display for the handheld interface; and 
     FIG. 19 illustrates the processing sequence of the command server to process and transmit message lists. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Overview 
     FIG. 1 illustrates a data retrieval/acquisition system according to the present invention generally illustrated by the reference numeral  1 . The instant system  1  includes a master server  2  which communicates with multiple remote input units  4  through a communications bus  6 . Each input unit  4  includes a communications server  12  directly connected to a command server  14  and data bases  16 . Each remote communications server  12  interactively communicates with one or more handheld user interfaces  8  while located within a predefined region  5  proximate thereto. This interactive communication is conducted through a wireless dedicated communication channel, such as upon an infrared carrier signal. 
     The communications server  12  controls all interaction between the handheld interfaces  8 , the command servers  14 , and the communications bus  6 . The command servers  14  control direct access to the databases  16 . The command servers  14  may implement any conventionally known IO management system, such as Pro-Tree (version 2.0), SQL or Paradox. The communications server  12  communicates with each handheld interface  8  through a unique communications protocol (hereafter referred to as the Handheld-Server Protocol). The communications server  12  communicates with the command servers  14  through a unique protocol (hereafter referred to as the Message List Protocol). 
     As explained below, the communications server  12  synchronizes its operations with those of the handheld interfaces  8  to minimize the excess data necessary for each transmission therebetween. The communications server  12  and interface  8  also utilize shorthand code values to identify constantly transmitted information, such as commands, user IDs, database IDs, and the like. By synchronizing operation of the handheld interface  8  and the corresponding communications server  12 , the instant system is able to avoid the need to transmit the user ID, time, date, authorization code, and the like during every transmission. 
     During operation, the user enters data at the handheld interface  8 , the data is transmitted to the communications server  12  and stored internally within the database  16 . Data may also be entered directly into the communications server  12 . Similarly, the user may request data previously submitted, in which case the communications server  12  accesses the corresponding database  16 , through the command server  14 , and transmits the necessary desired information to the requesting handheld interface  8 . Throughout operation, a backup copy may be maintained within the master server  2  for every remote database  16 . Additionally, the user may request, via the handheld interface  8 , data stored within a remote input unit  4  other than the data in the databases directly connected to the receiving communications server  12 . In such a circumstance, the corresponding communications server  12  would accept the request from the handheld interface  8 , determine that the desired information is stored within a remote database and request such information through the communications bus  6  from the communications server  12  containing the corresponding database. Thus, the communications bus  6  also allows data to be transmitted between communications servers  12  and between handheld interfaces  8  (such as when one doctor is requesting information from another doctor). 
     By way of example only, the instant acquisition/retrieval system  1  may be utilized within a healthcare facility wherein doctors, nurses, and staff utilize the handheld interfaces  8  to record and obtain patient information. These persons may be assigned different privileges which would allow varying levels of access to data. In this environment, each communications server may be located within a different ward or testing laboratory. Thus, a doctor in a general ward may need to send a message to, or obtain information from, a doctor or nurse in radiology. To do so, the doctor would transmit a request through the handheld interface  8 , with the request being received and decoded in the general ward&#39;s communications server  12 . The source/receiving communications server determines the appropriate destination communications server that corresponds to the destination handheld interface, into which the destination doctor or nurse has signed on. The desired message is transmitted to the radiology server, and to the corresponding handheld interface which queries the user through audio, video, or vibrating means. In a similar manner, the user within radiology may transmit a response through the corresponding radiology and general ward communications servers  12  to the requesting doctor&#39;s handheld interface  8 . Also, lab data may be quickly transmitted to a surgeon during an operation. 
     The instant acquisition/retrieval system  1  also allows doctors, nurses, and staff members immediate access to clinical data, even after clinic hours are closed. To do so, the user merely enters a request through his/her handheld interface  8 , which is transmitted through the corresponding communications server  12  to the clinical communications server  12 . The necessary clinical data is obtained from the clinical database and returned along the communications bus  6 . By way of example, the data acquisition/retrieval system  1  of the healthcare facility may be connected to similar systems via an ethernet connected between the master servers  2 . 
     The handheld interfaces  8  are used to enter all patient information such as personal information upon admittance, past medical histories, vital statistics throughout their stay in the hospital, and the like. For instance, these vital statistics may include systolic, diastolic, pulse, temperature, and respiratory information. Similarly, the handheld interface  8  may be used to enter information concerning the patient&#39;s fluid intake and output. 
     As will be explained below, the instant data acquisition/retrieval system  1 , also allows a user to carry a handheld interface  8  between regions (see the dashed line  5  in FIG. 1) dedicated to each communications server  12 . Optionally, when this occurs, the handheld interface  23 , is considered to have signed off with the old communications server (as illustrated by the dashed line  22 ). Thereafter, the handheld interface  23  must be signed onto the new communications server (as illustrated by the line  24 ) before it may be used for data entry. 
     The manner by which these objects and functions is achieved will become clear in connection with the following explanation of each module of the present invention. 
     Handheld Interface 
     FIG. 2 generally illustrates a block diagram of a handheld interface  8  having a display screen  30  which may be back-illuminated and which is controlled by a CPU  32  to display desired information thereon. The display screen  30  also functions as a touch pad and is sensitive to user contact. When contacted, the display screen  30  outputs a signal to the CPU  32  identifying the exact location of the contact therewith. The handheld interface  8  further includes a memory module  34  which stores software to control processing of the CPU  32  and which temporarily stores data received from, and transmitted to, the corresponding communications server  12 . The CPU  32  controls an IR interface  36  to control data transmissions to and from the communications server  12 . A bar code reader  37  is included to allow the user to enter customer or product information from a bar code, such as customer/patient ID and the like. 
     As explained below, the handheld interface  8  operates as an “event driven” device wherein the touch screen  30  is drawn to display a desired arrangement of virtual regions. Each region is assigned a unique identifier. The handheld interface  8  recognizes each contact by a user as an event. The contact/event is recognized with respect to the correspondingly defined region and the region identifier is returned. Thereafter, the CPU  32  identifies the necessary course of action based upon this identifier. 
     As illustrated in FIG. 3, during operation the CPU  32  may display a variety of menus, graphs, and the like upon the touch screen  30 . Within each display, the CPU  32  defines virtual regions which correspond to predefined processing sequences. The user initiates a desired event sequence by contacting the preferred region corresponding to the event. To facilitate the user interaction therewith, the CPU  32  provides multiple manners in which the user may enter and retrieve data. As illustrated in FIG.  3 ( a ), the CPU  32  draws a main menu  38  on the screen  30  and defines multiple menu selections  40  therein (see the flowchart of FIG.  10 ). Each menu selection  40  overlays and corresponds to a virtual event region  42  corresponding to a different event/case. Every screen  30  is displayed with an escape key  43  which allows the user to escape back to a previous function/screen or back to the main menu. 
     When implemented in a healthcare application, as illustrated in FIGS. 3 a - 3   d , when the user selects a vitals event region  44 , the CPU  32  recognizes it as such and processes a corresponding event sequence (see FIG.  13 ). 
     As illustrated in FIG. 3 c , the vitals input screen  60  (also referred to as the data I/O screen) displays current patient information in the patient field  62 , such as the patient&#39;s name, social security number, status, and the date upon which the vitals were last updated. The vitals input screen  60  illustrates the last current vitals (data sets) as shown in the systolic field  46 , diastolic field  48 , pulse field  50 , temperature field  52 , and respiratory field  54  (collectively referred to as data fields). The touch screen  30  allows the user to activate a desired vital sign field by selecting a corresponding icon  46 ,  48 ,  50 ,  52 , and  54 , respectively. Located immediately above each icon is the current value for the corresponding vitals field. This current value is also displayed within three rolling keys along side of the icon (the rolling keys are designated by the reference numeral  56 ). The patient&#39;s systolic vital sign field is active in FIG. 3 c , as evidenced by the inverted rolling keys  56 . Proximate the rolling keys  56  is a scroll bar  58  for illustrating in a bar format the current value of the active vital sign field (i.e., systolic) which is inverted to the current level (130). 
     To enter new patient vitals, the user may do so in multiple ways. First, the user may update the patient&#39;s systolic vitals by consecutively contacting each rolling key  56  to be incremented. Each rolling key continuously increments, such as from 0 to 9 and then back to 0. Alternatively, the user may enter patient vitals information by contacting the scroll bar  58  at the desired position. In accordance with the flowchart of FIG. 13, when the user contacts the scroll bar  58 , the bar is updated to reflect the newly entered value. If the user drags his/her finger along the scroll bar  58 , the CPU  32  will continuously update the level thereof to reflect this movement of the finger. The CPU  32  updates the corresponding rolling keys  56  for the active field (i.e., the systolic field as illustrated in FIG.  3 ( c )). The user may drag his/her finger across the scroll bar  58  until the desired value is displayed in the rolling keys  58 , at which time the user releases the scroll bar. The user may activate a different vital sign field (i.e., change the mode) by selecting the corresponding icon ( 46 ,  48 ,  50 ,  52 , and  54 ). 
     The vitals input screen  60  further includes change function keys  64  which afford the a user&#39;s direct access to displays, graphs, screens and the transmit function. More specifically, the vitals input screen  60  allows the user direct access to the fluids input screen (not shown) for the current patient by pressing the fluids function button  66 . Alternatively, the user may view the selected vital sign field (e.g., systolic field) in a graph format by selecting the view graph button  68 . The vitals input screen  60  further includes a transmit information button  70  which the user selects once a patient&#39;s new vital information has been entered. When the transmit button  70  has been pressed, the CPU  32  transmits the updated patient information to the communications server  12  in a format described below. 
     FIG.  3 ( b ) illustrates a graph corresponding to the present patient&#39;s systolic vitals which is displayed when the view graph button  68  is selected. 
     FIG.  3 ( d ) illustrates a patient inquiry screen  74  selected from the main menu  38  (also referred to as the data set inquiry screen). The patient inquiry screen  74  displays a scrolling text window  78  which exhibits the currently selected patient&#39;s name (data set header) and those names alphabetically proximate thereto. Along one side of the scroll text window  78  is positioned a scrolling bar  80  which includes an identifier  82  designating the position of the currently selected patient&#39;s name within a master alphabetical list. The user may scroll through the patient list by contacting the scrolling bar  80  at a desired location therealong. The top and bottom of the scrolling bar  80  corresponds to the beginning and end, respectively, of the list of patient names stored within the handheld interface  8 . 
     The patient inquiry screen  74  also includes a virtual keypad  76  which allows the user to enter the name of a desired patient. As the user selects each letter of the desired patient&#39;s name, the CPU  34  automatically performs a search upon the entered letters and updates the scroll text window  78  correspondingly. As the user enters additional letters, the CPU  32  concatenates these letters to the end of the search string it uses and again updates the scrolling text window  78 . The patient inquiry screen  74  also includes function buttons  64  along a bottom thereof to allow the user to automatically jump to an alternative screen. A scan button  77  is included to allow the user to read bar code data from a patient&#39;s wrist band, such as patient ID. 
     FIG. 18 illustrates an alternative scroll bar implementation which may be used to allow the user to enter alphanumeric information. For instance, the CPU  32  may control the display screen  30  to illustrate a display field  90  and one or more scroll bars  92 . The scroll bar  92  may be defined such that one end corresponds to the letter A while the opposite end corresponds to the letter Z. The CPU  32  would define multiple regions along the length of the scroll bar  92 , each region corresponding to one letter of the alphabet. When the user contacts the scroll bar  92 , a letter corresponding to the touched regions is displayed in a first location  94  of the display field  90 . 
     As the user drags his/her finger along the scroll bar, the letter displayed within the first location  94  will vary corresponding to the currently selected region. Once the user removes his/her finger from the scroll bar  92 , the last identified region is designated as the correct letter and entered in the first location  94  of the display. When the user again contacts the scroll bar  92 , the CPU  32  operates to display a corresponding letter in the second field location  96  of the display field  90 . 
     If it is desirable to enter numerals within the display field  90 , the CPU  32  may also draw a second scroll bar  98  upon the display screen  30 . The first end of the second scroll bar would represent a 0 while the second end of the scroll bar  98  would represent a  9 . The user would enter numerals in the display fields  90  in the same manner as discussed above with respect to letters. Optionally, a single scroll bar may be provided for letters and numerals with function buttons  100  and  101  being used to assign letters or numerals to the scroll bar. 
     FIG. 15 illustrates the RAM section  35  of the memory within the handheld interface  8 . The RAM memory  35  includes a patient information section  200  for storing a list of patient names (data set headers) and patient identifiers (data set identifiers) associated with the present user of the handheld interface  8 . The RAM memory  35  also includes a working space  202  for storing all other information entered by the user and transmitted between the handheld interface  8  and the communications server  12 . Each time the CPU  32  transmits a request to the communications server  12  for patient information, the CPU  32  redefines the current data structure within the working space  102  to correspond to the expected format of the return data from the communications server  12 . 
     By way of example only, when the CPU  32  requests patient vitals, it expects the returned data to include, in a preset order, the patient&#39;s social security number, date on which the patient vitals were last updated, and the most recent systolic, diastolic, pulse, temperature and respiratory values. The CPU  32  sets up fields within the working space  202  for each of these values. When the returned data is received, the CPU  32  parses through the returned packet and assigns bytes therefrom to the desired field in the working space  202 . 
     The RAM  35  further includes a temporary buffer for storing incoming and outgoing packets of information which are to be transmitted to and which are received from the communication server  12 . The CPU  32  moves data from the RAM  35  into the temporary buffer  204  immediately before transmitting this information and adds a packet header  206  thereto. 
     FIGS. 4-8 illustrate the processing sequence by which the CPU  32  controls the main menu, vital sign patient/data set input screen and the patient information screen (FIGS. 3 a - 3   d ). 
     Generally, during operation the CPU  32  loops through one of two primary case/event handling loops (FIG.  4 ). The first case/event loop operates to draw the main menu (FIG. 3 a ) and to handle events chosen from the main menu. When an event occurs which corresponds to a defined key region within the main menu, a corresponding event identifier is returned as the calling identifier. A return code is set equal to this calling identifier and the return code is checked against a predefined value (0). If the return code is non-zero, processing flow enters the second primary loop to call the corresponding event handling function. The second primary loop corresponds to processing in which a menu other than the main menu is displayed (FIGS. 3 b - 3   d ). During this second loop, a code which identifies the next function to be performed is continuously checked. When the code equals zero, processing returns to the main loop. When the code is a nonzero value, the corresponding function is called. Once each function is completed it returns a code identifying the next function to be performed by the user. This configuration reduces the memory requirements by reducing the levels of functions to be called, thereby reducing the necessary stack space. 
     FIG. 4 generally illustrates the processing undergone by the handheld interface  8  when the user initiates the first session (i.e., when the user first logs in). When a session is initiated the handheld unit prompts the user for the user&#39;s ID and password (step  1602 ). Next, a packet is constructed in the temporary buffer  204  which contains a long header  206  structure and having a data section including the user ID and password (step  1604 ). This packet is transmitted (step  1606 ) and a validation code therefor is waited upon. If the validation code is not received (step  1608 ) processing returns to step  1602  in which the user is reprompted for the ID and password. If a validation code is received, processing continues to step  1610  in which a return code is set to indicate that processing should move to the patient inquiry module. Thereafter, the return code is tested to determine whether it equals zero (step  1623 ). If the return code equals zero, processing returns to step  1614  in which the main menu is redrawn. 
     After this initial login sequence is completed, flow enters the main event handling loops. First, a main menu is drawn and key regions therein are defined in steps  1612  and  1614 , after which the system waits for an event to occur (step  1616 ). Once an event occurs, it is determined whether the event is within a defined menu regions  42  (step  1618 ) (i.e., whether the user has touched the display screen  30  at a location corresponding to a menu selection  40 ). If not, processing loops back to wait for the next event. If so, an event identifier is obtained for the key region in which the event occurred (step  1620 ). Next, an event handling function corresponding to the event identifier is called (step  1622 ). Thereafter, processing waits for a call identifier returned from the called event handling function. A return code is set equal to the call identifier (step  1623 ) and the return code is tested in step  1624  and if zero, processing returns to the initial step  1612  to redefine and redraw the main menu. If the return code does not equal zero, the process determines that the user has selected another function besides displaying the main menu. Thus, the event handling function corresponding to the non-zero return code is called (step  1626 ). Thereafter, the main event handling loop waits for the called function to return a call identifier which is tested in step  1624 . 
     FIGS. 5 and 6 illustrate the process undergone when the patient information screen  74  is selected to be displayed (such as during the wake up function or when called by the user). First, an initialization routine is called in step  1700  (steps  1710 - 1720  in FIG.  6 ). This initializing process begins by determining whether the handheld interface  8  includes a list of patient names (data set headers) and IDs (step  1710 ). If this list does not exist (such as when the handheld interface has initially been woken up), the unit constructs and transmits a packet to the communications server  12  requesting the patient list associated with the currently signed-in user (step  1712 ). The communications server  12  receives this packet, identifies the user ID, and requests the appropriate information from the command server  14 . Thereafter, the appropriate database  16  is read and the patient list for the user is transmitted back to the handheld interface  8 . After the interface  8  sets up the data structure in the patient memory  200  for the patient list (step  1714 ), it waits for the returned patient list (step  1716 ). Once the patient list (name and ID) is received, it is stored in the patient memory  200 . 
     The handheld interface  8  may not include sufficient display space in the scrolling text window  78  to show an entire patient&#39;s name. Thus, the patient memory section  200  will only include sufficient memory to store the maximum number of characters which may be displayed for a single patient name upon the screen. Once the patient list is stored, the patient screen format is displayed (step  1718 ) as illustrated in FIG. 3 d . Next, the patient names are displayed in the scrolling text window  78  (step  1720 ) (FIG. 3 d ). When the patient list is too long to be completely displayed within the scrolling text window  78 , a default portion thereof is displayed. Next, the system waits for an event (step  1722 , in FIG. 6) and when one occurs, an event identifier is assigned thereto. 
     The event identifier is passed to a case/event statement which includes every possible valid value for the event identifier. By way of illustration, processing will continue along one of six possible processing paths to blocks  1724 ,  1726 ,  1728 ,  1730 ,  1750  or  1756 , depending upon which event occurred. When event  1724  occurs (i.e., the user presses the escape icon), the system returns a zero calling identifier to the main loop (thereby indicating that no new event handling function has been selected). If the event indicates that the user has touched the scrolling bar  80 , processing flows to box  1726  in which the system determines the exact location of the event (step  1732 ). This location is correlated with a pointer that is used as an index into the patient list to identify the new patient to be displayed in the scrolling text window  78 . Once the event location is determined, the pointer into the patient list is updated and the scrolling text window  78  is redrawn to display the name of the selected patient and a limited number of patient names surrounding the selected name (step  1734 ). 
     Next, the scrolling bar  80  is updated to move the identifier  82  to a new position identifying the relative location of the indexed patient within the overall patient list (step  1736 ). Thus, if the first patient is selected, the identifier  82  is redrawn at the top of the scrolling bar  80 , and if the last patient is selected, the identifier  82  is drawn at the bottom of the scrolling bar  80 . If the event is identified as occurring within the scrolling text window  78 , processing flows to step  1728 . Specifically, the location of the event is again identified (step  1738 ) relative to the names currently displayed. The name closest to the event is identified as the selected patient. Thereafter, the pointer into the patient list is updated to index the newly selected patient name (step  1740 ). This name is displayed in the center of the scrolling text window and, optionally, may be inverted in color (step  1740 ). The identifier  82  within the scrolling bar  80  is also redrawn to properly identify the new position of the selected patient within the patient list (step  1740 ). 
     If the keypad  76  is touched, processing flows to block  1730 , at which the letter is identified which corresponds to the region touched (step  1742 ). This selected letter is added to a temporary patient searching string within the work space memory  102  (step  1744 ). This letter is added to a search string (which is empty until the first letter is selected). Thereafter, the processor conducts a search based upon the search string into the patient list to identify the name most closely corresponding to the letter(s) selected from the virtual keypad  76  (step  1746 ). If a search string exists (i.e., the user has already entered some letters) the newly selected letter is concatenated onto the search string and a new search is conducted upon the text strings within the patient list to find the first text string which is greater in alphabetic value than (i.e., closest to) the search string. The pointer is set to the closest patient name and the scrolling text window  78  and the scrolling bar  80  are updated (steps  1746  and  1748 ). If the user wishes to delete a letter from the search string, he/she simply pressing the delete region key. 
     If the user selects the scan region  77 , processing flow moves to block  1750 . The bar code scanner is read to obtain the bar code scanned by the user (step  1752 ) (this bar code may appear on a patient&#39;s wrist band and the like). The bar code includes the patient ID, which is used to find the patient name within the patient list (step  1754 ). Next, the pointer into the patient list is updated (step  1756 ) and the scrolling text window  78  and scrolling bar  80  are redrawn (step  1758 ). 
     Once the user has selected a desired patient, the user may escape from the patient inquiry screen by pressing the escape icon  43  in the upper left corner or by selecting one of the function  64  buttons at the bottom of the screen (step  1760 ). As illustrated in FIG. 3 d , the user may escape to the main menu, review a patient&#39;s information complete record or review the patient&#39;s vitals. If the user presses one of the change function buttons  64  at the bottom of the screen, the corresponding event identifier is evaluated to determine which function key the user has selected (step  1762 ) and the corresponding return code is returned to the main processing loop in FIG. 16 (step  1764 ). 
     FIGS. 7 a ,  7   b  and  8  illustrate the processing sequence undergone by the handheld interface  8  when the vitals/data input/output handling function is chosen (i.e., when a user desires to enter patient vitals). First, the display screen is cleared (step  1800 ) and the vitals (data I/O) format is drawn upon the screen (step  1802 ). Similarly, the key regions are defined which correspond to each even identifier. Next, it is determined whether the workspace memory contains vitals for a selected patient (step  1804 ). If not, the processor constructs and transmits a packet (step  1806 ) requesting patient vitals. Thereafter, the workspace memory  202  is set up in the data structure corresponding to patient vitals (step  1808 ). Thereafter, the handheld interface waits for the returned patient vitals, receives these vitals in one or more packets and disassembles the packets and stores the patient vitals in the workspace (step  1810 ). Next, the processor draws the patient vitals onto the screen (step  1812 ) and sets the default mode to a predetermined field (e.g., systolic field). The vitals for the default field are drawn into the scroll bar (step  1814 ) and the default rolling keys  56  corresponding to the default field are inverted. Thereafter, the handheld interface waits for an event to occur (step  1816  in FIG. 7 a ) and when it occurs, identifies the event number corresponding thereto. 
     Processing flows along one of six paths depending upon which event number is identified. While each field upon the vitals screen corresponds to a separate event number, the events as displayed in FIG. 8 may be grouped into six general categories, namely, touching a roll key, touching the icon, touching the scroll bar, touching the patient&#39;s general information, touching the escape key, and touching the change screen buttons (blocks  1818 ,  1830 ,  1840 ,  1852 ,  1858  and  1864 ). Once the event number is identified as corresponding to a rolling key  56 , it is determined whether the touched rolling keys are active (step  1819 ). If not active, processing returns to step  1816 . If active, a pointer is determined which identifies the field within the workspace memory  202  which corresponds to the specific roll key/vital sign selected (step  1820 ). 
     Next, the data value identified by the pointer into the workspace is incremented by a 1, 10, 100, etc. depending upon the rolling key which was touched (step  1822 ). Thus, referring to FIG. 3 c , if the user presses the center rolling key corresponding to the systolic field, the systolic data value within the workspace memory will be incremented by 10. Similarly, if the diastolic field is selected and the user presses the leftmost rolling key therein, the processor will increment the diastolic data value within the workspace memory by 100. Next, it is determined whether or not the incremented value has created an overflow and if so, the incremented digit is rolled-over (step  1824 ). This rollover function is performed to rotate a rolling key having a current value of 9 to a new value of 0. 
     Thus, if the user selects the pulse vital and contacts the “1s” rolling key (which has a present value of 9), the processor will update the pulse value within the workspace memory to “80”. Thereafter, the new vital sign is drawn into the rolling keys  56  which have been updated and the new vital sign is stored in the corresponding field in the workspace memory (step  1824 ). Finally, the processor updates the scroll bar  58  to reflect the change in the current data value (step  1826 ). 
     If the event identified in step  1816  corresponds to an icon, processing proceeds to step  1830 . First, the rolling keys are deactivated for the previously active vital sign field (step  1832 ) and the rolling keys for the newly chosen vital sign are activated (step  1834 ). Next, the rolling keys for the deactivated and newly activated vital sign fields are inverted to display the newly active field to the user (step  1836 ). Thereafter, the scroll bar  80  is redrawn with parameters, ranges and current vital signs corresponding to the newly selected vital sign field (step  1838 ). 
     When the identified event corresponds to touching the scroll bar  80 , process flows to step  1840 . Once the scroll bar is touched, the exact location of the event is determined therein and used to identify the corresponding vital sign value (step  1842 ). Then, a pointer is determined which identifies the vital sign data value within the workspace memory which corresponds to the active vital sign field (step  1844 ). This vital sign data value is updated to the new vital sign value selected within the scroll bar (step  1846 ). Thereafter, the active scroll keys are updated with the new data value (step  1848 ) and the scroll bar is inverted to reflect the new data value (step  1850 ). When the event occurs within the patient information region, processing flows to step  1852 . In such a case, the patient information screen is redrawn. To do so, a calling identifier is set to correspond to the patient information screen (step  1854 ) and control is returned to the main loop (step  1856 ). 
     Optionally, when the user touches the patient information region, a pop-up window may appear and query the user as to whether it is desirable to go to the patient information screen or enter a patient identifier through the bar code reader. In either case, if the user touches the patient information region, before new patient vital signs have been transmitted to the communication server, the user is prompted as to whether or not these vital signs should be transmitted. When the escape icon is touched, processing flows to step  1858 , after which the calling identifier is set to zero (step  1860 ). Processing is returned to the main loop (step  1862 ). 
     If the screen changing buttons are touched, processing flows then to step  1864 , after which the selected button is determined (step  1866 ). In step  1867 , it is determined whether the event corresponds to the transmit button. If the selected button corresponds to the transmit button, the current patient vitals are constructed into a packet format and transmitted to the communication server  12  (step  1868 ). If the selected button does not correspond to the transmit button, the calling identifier is set equal to the newly selected screen (step  1870 ). Thereafter, control is returned to the main loop (step  1872 ). 
     When the return code within the main loop is set to correspond to the view graph display screen (FIG. 3 d ), the processor determines the active vital sign field (e.g., systolic field), and obtains the corresponding default parameters for the graph. Thereafter, the screen is cleared and a graph having the parameters for the active vital sign field is drawn. Next, the vital sign data values for the active vital sign field are read from the workspace memory and used to draw the graph. 
     Optionally, in the view graph screen a series of changing function buttons may be displayed along the bottom thereof. These buttons would allow the user to automatically select another vital sign to view in a graph format without intermediately returning to the vital input screen. 
     In accordance with the above procedure, the handheld interface  8  allows for user inputs and displays patient information to the user. 
     Interface-Server Protocol 
     Once the user enters the desired data and wishes to send this data to the communications server  12 , the user presses the transmit function button  70 . Once the CPU  32  identifies that an event has occurred which corresponds the transmit function button  70 , the main loop (FIG. 4) calls the transmit handling function. FIG. 4 illustrates the process by which the CPU  32  transmits data to the communications server  12 . 
     As illustrated in FIG. 9, each transmission comprises an information packet  300  of IR signals corresponding to a packet of data, wherein every packet is constructed with the same predetermined length (e.g., 128 bytes) and in one of two formats. This length is software and operative system definable and may vary. Certain messages transmitted between the handheld interfaces  8  and the corresponding communication servers  12  comprise an amount of data which is unable to be assembled into a single packet. Thus, in such circumstances the transmitting device segments the data into a plurality of equal length packets  300  (referred to as frames). The series of frames form a message  302 . 
     When transmitting a message the first packet/first frame thereof is constructed with a header section  304  formed in a long header structure followed by a data field  306 . The long header  304  includes a 4 byte command field  308 , a 6 byte user identifying field  310 , and a 4 byte message total field  312 . The command field  308  identifies the process to be performed upon the subsequent data, the user ID identifies the user signed into the handheld interface  8  transmitting or receiving the packet  308  and the message total  312  identifies the total length of the message which will follow. This total length includes all bytes within subsequent packets  300  corresponding to this specific message  302 . Thereafter, a data field  314  (having 114 bytes in a packet with a 128 byte structure) follows. 
     If the message includes more data than will fit in a single packet, subsequent packets/frames are transmitted. These subsequent packets/frames are constructed with a short header structure  316  preceding the data segment  318 . The short header  316  includes a 4 byte command  320  and a 4 byte positioning packet  322  identifying number to enable the receiving device to determine the position of the packet within the overall message. Packets containing a short header  316  includes a 120 byte data field for a packet formed with 128 bytes. During transmission, the first packet of each message includes a long header  304  structure followed by a data field, with each subsequent packet within the message including a short header  316  instructed followed by a data field. In this manner, the device is able to increase the amount of data transmitted within each packet for long messages. The transmitting device need not send the user ID and the message total more than once for a given message since the receiving device is able to associate corresponding packets with a single message  302  based on the packet number  322  and communication channel. 
     To transmit a message (FIG.  10 ), the CPU  32  reads the current data from the workspace memory  200  in the RAM  35  (step  400 ). Next, the CPU  32  determines the length of the message and the ID of the user signed in to that handheld interface  8  (step  402 ). The CPU  34  constructs a packet header formed with the long header structure (step  404 ). The CPU  34  clears the packet number (step  406 ) and writes the data to the transmit buffer (step  408 ). If the packet is full (step  410 ), the CPU  32  transmits the packet and clears the buffer (step  412 ). If the packet is not full, it determines if more data exists to write to the buffer (step  414 ). If no more data exists, it transmits the packet. If more data exists, it again writes to the packet. In step  416 , it is determined if more data exists, and if not it exits. If so, the packet number is incremented (step  418 ). Next, the CPU  34  constructs a partial short header for the second frame to be transmitted in this message (step  420 ). The partial header includes the code for the corresponding command and the current packet number. Thereafter, the next segment of data is written to the packet (step  408 ) and steps  410  through  420  are repeated. Once the last packet is transmitted (step  414 ) and it is determined that no more data remains to be written to the packet (step  416 ), the system exits the transmit routine (step  422 ). 
     Communication Server 
     FIG. 16 illustrates a block diagram of the communication server  12 . The communication server  12  includes an IR receiver/transmitter  100  which receives and transmits IR communication packets from and to the handheld interface  8 . The IR receiver transmitter  100  operates in conjunction with an I/O card  102  to store a packet of information from each communication channel in the corresponding address within a temporary buffer  104 . Each communication channel corresponds to a unique handheld interface  8 . For instance, the communication server  12  may provide for 128 IR channels and thus, the temporary buffer  104  will include 128 buffer locations, with each buffer location having sufficient memory to store a complete IR packet  300  (FIG.  9 ). The number of channels is locally definable and may be any desired number. The array locations within the temporary buffer  104  store the IR packets in the format transmitted from the handheld interface  8  as described above. 
     The communications server  12  further includes an input buffer  108  which represents a storage space used by the CPU  106  when converting packets from the format stored in the temporary buffer  104  to message lists with a different format to be transmitted to the command servers  14 . The input buffer  108  represents an array, each element of which includes the COM_INFO structure (explained below). 
     Each element of the input buffer  108  array is accessed based on the device number. Thus, if 128 handheld interfaces  8  are being used, the input buffer  8  will include 128 elements. The communications server  12  further includes a message buffer  110  which is utilized to store the actual data for each complete message sent from the hand held interface once all of the necessary packets have been transmitted by the handheld interface  8  and reassimilated by the CPU  106  into a single message. The COM_INFO stored in the input buffer  108  includes a pointer MSG_From_HH into the message buffer to the beginning of the corresponding data string. Once every packet  300  for a message  302  is received and the corresponding data is stored in the message buffer and the COM_INFO is stored in the input buffer  108 , the CPU  106  constructs a message list therefrom. Each message list to be processed by the command server  14  is stored on one of a process queue  114 . The message list includes a pointer to the corresponding data string in the message buffer  110 . Each message list received from the command server  14  is initially stored in a transmit queue  116  prior to being converted back into packets  300  and transmitted to the handheld interface  8 . The message list includes a pointer to a corresponding data string which is stored in the message buffer  110  when it is received from the command server  14 . 
     The process and transmit queues are operated in a first-in-first-out sequence such that each message is processed or transmitted in the order in which it is placed in the queue. The transmit and process queues  112  and  114  constitute dynamic queuing systems which attach message lists in a linked list structure. Each message list include the data structure illustrated below: 
     
       
         
               
             
               
               
               
               
               
               
             
               
             
               
               
               
               
               
               
               
               
             
           
               
                   
               
             
             
               
                 MESSAGE LIST 
               
               
                   
               
             
          
           
               
                 COM —   
                 Data 
                 Command 
                 MSG —   
                 MSG_LEN 
                 Prev 
               
               
                 INFO 
                 File 
                 (1) 
                 TO_HH 
                 (Long 
                 MSG_LST 
               
               
                 10 
                 (Integer) 
                   
                 (Pointer) 
                 Integer) 
                 (Pointer) 
               
               
                   
               
             
          
           
               
                 COM_INFO 
               
               
                   
               
             
          
           
               
                 Device 
                 CMD 
                 Packet 
                 User 
                 User 
                 MSG 
                 MSG 
                 MSG 
               
               
                 Number 
                 (4) 
                 Number 
                 ID 
                 ID 
                 Total 
                 Length 
                 From 
               
               
                 (Integer) 
                   
                 (Long 
                 To 
                 From 
                 (Long 
                 (Long 
                 HH 
               
               
                   
                   
                 Integer) 
                 (6) 
                 (6) 
                 Integer) 
                 Integer) 
                 (Pointer) 
               
               
                   
               
             
          
         
       
     
     The message list data structure includes a first section COM_INFO dedicated to, and containing information concerning, messages received from the handheld interface  8 . The next four fields represent fields which are created immediately before transmitting a message list to the command server  14  and another communications servers  12 . The final field (Previous MSG_LST) is used as a pointer to the subsequent message list within the queue to be processed. The first section COM_INFO includes a device number uniquely identifying the handheld interface transmitting the message. The device number is generated by the I/O card  102  when the CPU  32  requests a packet  300  from the temporary buffer  104 . The device number is produced depending upon the communications channel being accessed. The command (CMD) includes the structure of the CMD field transmitted in the header of each packet  300  (i.e., the 2 byte database ID, 1 byte command ID, and 1 byte reserved). 
     The command (CMD) represents the command to be processed in accordance with the corresponding message being transmitted to or from the handheld interface  8 . The 4 bytes within the command are separated such that the first two bytes identify the database to be processed when performing the command, the third byte stores a number corresponding to the specific command to be performed, and the fourth byte is reserved. By way of example, with respect to the third byte, numerals  1 - 127  represent commands to be processed by the command server, while numerals  128 - 255  represent a command from the handheld interface  8 . As noted above, the use of shorthand code numbers for specific commands reduces the amount of data to be transmitted to and from the handheld interface  8 . 
     The Packet Number is a long integer which is incremented each time a packet is appended to a message on the input buffer  108 . The User_ID_To is a 6 byte value added by the handheld interface  8  to identify a destination user. If set to zero, the destination is the communications server. The communications and command servers determine which server to send the command to. This value if non-zero will identify the user of a handheld interface  8  desiring to communicate therewith. The User_ID_From is a 6 byte value added once at login time. This user ID is assigned to the channel to identify who is logged in at that channel. This value is maintained until the person signs out. Thus, the user ID will only be transmitted once during a login session. The communications server  12  keeps track of each User ID signed onto handheld interfaces served by that communications server  12 . The message total length (MSG_Total) is a value assigned by the handheld interface  8  or by the command server  14  when a message is transmitted. The message length (MSG_LEN) is a value updated by the short and long header parsing functions to keep track of the length of a message in the message buffer  110  as the packets for the message are added thereto. The message length field is initially tested by the communications server  12  when processing each packet in the temporary buffer  104  to determine if the packet is in a long or short header form. The message pointer field (MSG_From_HH) is a pointer into the message buffer to the location of the actual data message. The MSG_From_HH pointer is updated each time a new packet is appended to a message. 
     The message list structure includes the above COM_INFO structure as in addition to a Data_File field that represents an integer identifying the database, written from the COM_INFO structure, to be processed in connection with the corresponding command. The command (CMD) field represents a one byte command, written from the COM_INFO structure, to be processed. The MSG_To_HH field represents a message pointer used to point to the data compiled by the command server in connection with this message which will ultimately be sent to the handheld interface  8 . The MSG_LEN field represents a long integer identifying the current length of the data corresponding to the message and stored in the message buffer. The Previous_MSG_LST represents a pointer pointing to the next message to be processed. The previous message pointer enables the system to accomplish dynamic queuing for the process and transmit queues. 
     FIG. 11 illustrates the processing sequence by which the communication server  12  receives messages from the handheld interface  8 , processes these messages and transmits these messages to the command server  14 . First, the I/O card  102  is initialized, along with the communication channels, buffers and queues (step  700 ). Next, the data structures for the message list, COM_INFO, CMD, and short and long headers are set up (step  702 ). A current channel to be read by the I/O card  102  is initialized to the first channel (step  704 ). Next, the current channel is tested to determine whether data is being transmitted thereon from the corresponding handheld interface  8  (step  706 ). If data is present, the packet of transmitted data is read and stored in the temporary buffer  104  (step  708 ). The packet of data is stored within the temporary buffer  104  at the array address corresponding to the current channel. A channel identifying number corresponding to the transmitting handheld interface  8  is also assigned thereto by the I/O card  102 . 
     Next, a check sum field within the data packet is tested to determine whether the transmitted data is valid (step  710 ). If the data is invalid, the communication server takes the necessary corrective actions (step  712 ). If the data is valid, the CPU  106  requests the channel number (step  714 ) and the packet  300  from the I/O card  102  and utilizes the channel number to index the correct corresponding element within the input buffer  108 . Next, it is determined whether a packet is an initial frame or a subsequent frame of a message (step  716 ). To effect this test, the message total field, within the element of the input buffer  108  corresponding to the current channel, is read and compared to zero. If the message total field equals zero, then a packet has not yet been written to this element of the input buffer  108 . Thus, the packet being read is identified as an initial packet which will include the long header structure. Otherwise, the packet is identified as one containing the short header structure. In either case, the packet number is incremented within the currently indexed element of the input buffer  108 . 
     If the packet contains the long header structure, processing moves to step  718  in which the parse long header function is invoked. If the packet includes the short header structure, processing moves to step  720  where the parse short header function is invoked. 
     FIG.  12  and FIG. 13 illustrate the parse long and short header functions. Within the parse long header function, the first four bytes of the data packet within the temporary queue is read as the command (step  722 ). This command is compared with a list of valid commands and if the command is invalid the processor takes the necessary corrective action (step  724 ). If the command is valid, the command is written to the command field within the element of the input buffer  108  indexed by the corresponding channel number (step  726 ). Next, the subsequent six bytes of the packet within the temp buffer is read as the User ID, if present, of the destination user for the attached message/data. This six byte ID is stored in the User ID_To field of the element within the input buffer  108  indexed by the current channel number (step  728 ). The User ID, corresponding to the signed on user, is added to the UserID_From field of the indexed element. 
     Next, the subsequent four bytes are read from the packet within the temporary buffer  104  as the total length of the following message (e.g., the total number of bytes to follow within one or more packets corresponding to the present message) (step  730 ). The four byte value representing the message total is converted to a long integer (step  732 ) and assigned to the message total field within the element of the input buffer  108  indexed by the current channel number (step  734 ). Thereafter, the data section within the packet is written to the message buffer as a data string and the length thereof is stored within the message length field within the presently indexed element of the input buffer  108  (step  736 ). 
     A message pointer pointing to the data string within the message buffer  110  is stored within the message pointer field of the indexed element within the input buffer  108  (step  738 ). Finally, the element of the temporary buffer  110  is cleared (step  740 ). In this manner, steps  718 - 740  parse through a packet having a long header structure, create the COM_INFO structure within the input buffer  8  and store the message  302  from the handheld interface  8  within the message buffer  110 . 
     Returning to FIG. 11, if in step  716  it is determined that the packet is not an initial packet, then the short header function is invoked (see FIG.  13 ). First, the first four bytes of the packet are pulled (step  742 ) and compared with the value in the command field of the currently indexed element within the input buffer  108  (this command is indexed based on the channel number) to determine if these commands are the same (step  744 ). If not, the system takes the necessary corrective actions (step  746 ). If the commands correspond, the packet number within the short header is pulled (step  746 ), converted to a long integer (step  748 ) and compared to the packet number (plus one) within the indexed element of the input buffer  108  (step  750 ). These packet numbers must correspond to ensure that the received packet is the next packet to be added to the input buffer  108 . If the packet numbers correspond, the present packet is identified as part of the message corresponding to the presently indexed element within the input buffer  108  and processing flows to step  752 , else it returns. If the packet is not matched based on above criteria, then a corrective action is taken. 
     Next, the data within the temporary buffer  110  is pulled (step  752 ) and the portion of the message already stored in the message buffer  110  is read (step  754 ). The new data is added to the end of the stored message and the new total string is rewritten to the message buffer  110  (step  756 ). The message pointer (MSG_From_HH) and the message length (MSG_LEN) are updated within the corresponding fields of the COM_INFO of the indexed element of the input buffer  108  (step  758 ). Thereafter, the control returns to the main process (step  760 ). 
     Referring to FIG. 11, once control is returned to the main program, the current channel is incremented (step  760 ). Next, it is determined whether all channels have been checked (step  762 ). If so, control is set to the processing sequence (at point A). If all of the channels have not been checked, control returns to step  706 . This process is continuously performed until all of the channels have been checked thereby transferring all packets of data from the temporary buffer  104  to the input buffer  108  and message buffer  110 . 
     Next, processing moves to the processing queue sequence (FIG. 14) to move completed messages  302  to the processing queue  112 . First, the current element pointer into the input buffer  108  is set to the first input buffer element (step  800 ). Then, it compares the message total length (MSG_Total) with the message length (MSG_LEN) to determine whether a complete message corresponding to the current element within the input buffer  108  has been received and stored in the message buffer (step  802 ). If not, the incomplete message remains on the input buffer  108  and the current element pointer is incremented (step  804 ) and the process returns to step  802 . 
     If the complete message for the current element has been received, the message is placed on the processing queue (step  806 ) by creating a message list therefor. To do so, the command information (COM_INFO) of the current element of the input buffer  108  is written to the processing queue  112  and stored in the command information (COM_INFO) section therefor. As the corresponding message represents a transmission from the handheld interface  8  to the command server  14 , the next four fields of the indexed message list element in the processing queue remain undefined. This message list is “pushed onto the back” of the processing queue by storing, in the preceding message list in the processing queue, a pointer to the current message list. This pointer is stored in the final field (Previous_MSG_LST) within the previous, most recent message list added to the processing queue (step  806 ). 
     Once the command information has been moved to the processing queue, the corresponding element of the input buffer  108  is cleared (step  808 ). Thereafter, the current element pointer into the input buffer  108  is incremented (step  810 ) and it is determined whether or not every element of the input buffer  108  has been tested (step  812 ). If not, processing returns to step  802  and the next element within the input buffer  108  is processed. If processing is done on the input buffer  108 , control moves to the process the message lists on the processing queue. 
     The first element of the processing queue is tested to determine whether a command is stored therein (steps  900  and  902 ). If a command exists on the processing queue, this command is “dequeued” (step  904 ) by reading the message information from the processing queue (which is stored in the message list structure). The command field (CMD) within the COM_INFO section of the message list is read. The message is parsed into specific components (step  906 ), by reading the first two bytes of the command field, converting these bytes to a long integer form and storing the data base identifier in the Data_File field of the message list (step  908 ). Next, the third byte of the command (CMD) field in the COM_INFO structure is read and stored in the Command field of the message list (step  910 ). Then the actual data message is appended to the message list structure based on the message pointer (MSG_TO_HH) and the message length (MSG_LEN) are reset (step  912 ). The communications server  12  sends the message to the appropriate command server  14  based upon the database and command code (step  912 ). 
     Next, the previous message pointer (Previous_MSG_LST) is read from the current message list to determine the next message to be processed on the queue (step  914 ) and control is returned to step  902 . In this manner, each message upon the processing queue  112  is parsed through and transmitted to the appropriate command server  14 . When no more commands are on the processing queue, control is moved to the create transmit queue module (step  916 ) (FIG.  15 ). 
     FIG. 17 illustrates the process by which the communication server  12  processes messages upon the transmit queue which are to be sent to the handheld interface  8 . First, the first message upon the transmit queue is tested (step  1000 ) to determine whether data is contained therein (step  1002 ). If data exists, the message is dequeued by taking the message off the transmit queue (step  1004 ). Next, the command information from the message list is read and a long header constructed for the first packet to be transmitted to the handheld interface  8  for the message (steps  1008  and  1009 ). Next, the data from the message is written to the packet and transmitted (step  1010  and  1012 ). Thereafter, it is determined whether additional data remains to be transmitted to the handheld interface  8  (step  1014 ). If yes, a short header is constructed (step  1015 ) and additional data from the message is written to the packet containing the short header (step  1016 ). 
     Once constructed, the packet containing the short header is transmitted (step  1018 ) and processing returns to step  1012  at which it is determined if more data remains. This loop is repeated until the entire message has been transformed from the message list structure into data packets and transmitted to the handheld interface  8 . Once the entire message has been transmitted, control passes to the next module (step  1020 ). 
     The communications server  12  tests the communication bus  6  and determines if messages have been sent from other communication servers. First, the communications bus is tested to see if a message exists (step  1100 ). If a message exists, the message is read (step  1104 ) and the command therefor is decoded (step  1106 ). Thereafter, the command is tested to determine whether the message should be transmitted to a corresponding handheld interface  8  or whether the message should be transmitted to a command server connected to the communication server  12  (steps  1108  and  1110 ). Thereafter, the message is placed on the transmit or processing queue depending upon the destination of the message (steps  1112  and  1114 ). Thereafter, control is returned to the main program (step  1116 ). This process is continuously repeated until the communication server  12  is turned off. Once turned off, the communications channels are closed and the system is turned off. 
     Command Server 
     The command server operates to update the corresponding databases based upon messages received from the communications server. The command server utilizes a conventional software package for managing these databases, such as Pro-tree (version 2.0). Other database managing systems may be used to access the data base, such as DBase, CodeBase, B-Trieve, Cisam and the like. Particular commands within the conventional management system are called depending upon the command code and database codes transmitted within the message list. 
     FIG. 19 illustrates the process by which the command server  14  invokes the database management functions. First, the command server  14  receives a message (step  900 ), including the complete message list structure followed by the data message. Next, the command server  14  reads the data base file field (step  902 ) and determines whether that data base code is valid for the present command server  14  (step  904 ). If not, it returns an error message (step  906 ). If so, control is transferred to the database routine corresponding to the command code (CMD) in the Command field of the message list (step  908 ). Next, it is determined whether the command code is correct for the addressed database (step  910 ). If not, it returns an error code (step  906 ). If so, it accesses the message data within the message list and performs the appropriate operation upon the data base (step  912 ). Thereafter, it constructs a return message using the data returned from the database into the structure of the message list (step  914 ) and quits (step  916 ). 
     To invoke the database managing functions, the command number is processed within a case statement, whereby each case within the case statement corresponds to a unique command number. Each case statement calls the appropriate routines. For instance, command number  7  may represent an add command, and thus, case “ 7 ” would direct the command server to read the data from the message and write this data to the next address within the database. Similarly, the command number within the message may represent a read or request operation, in response to which, the corresponding case would direct the command server to read the desired information from the database corresponding to the user ID transmitted within the message. The command server thereafter adds this data to the message and retransmits it to the communications server. 
     From the foregoing it will be seen that this invention is one well adapted to attain all ends and objects hereinabove set forth together with the other advantages which are obvious and which are inherent to the structure. 
     It will be understood that certain features and subcombinations are of utility and may be employed without reference to other features and subcombinations. This is contemplated by and is within the scope of the claims. 
     Since many possible embodiments may be made of the invention without departing from the scope thereof, it is to be understood that all matter herein set forth or shown in the accompanying drawings 1-19 is to be interpreted as illustrative, and not in a limiting sense. 
     The following appendix sets forth descriptions of the modules and functions used by the present system. 
     Glossary 
     key—an area of the screen that has been registered with the opening system as an area where an event is expected. If an event does not occur within this area, an integer identifier will be returned by the operating system indicating that the event did occur. 
     event—the screen was touched, if it was touched in an area defined by a key, then return the identifier. 
     scrolling text window—a key where scrolling text will reside. 
     scroller—a key associated with the scrolling text window, the scroller has a bar in it to indicate where the text within the text window is in relationship to the rest of the text. 
     scrollbar—the tool used for entering vitals (darkened from the very bottom of the key to the value chosen by the user). 
     rolling key—a key with a digit in it, when the key is touched, that digit is incremented. If the digits value is 9 and it is incremented, it will contain the value 0 with no carry performed. 
     Module 
     scrollbar.c—contains all functions for the scroll bar 
     functions to be used by other modules. 
     init_scroll_bar—initializes all necessary variables and draws all of the detail. 
     get_scroll_bar_value—upon an event in the scroll bar key, this routine is called and it handles that event, then it returns the value and that the scroll_bar is pointing to (the value point pointed to by the user). 
     set_scroll_bar_value—the user can set the value anytime. 
     functions to be used internally by this module 
     draw scroll_bar—draws the inside of the scroll_bar. 
     Module 
     vital_input—contains all the functions used to perform the vital input 
     note—the Mode value indicates what is being input at the moment, if the user has chosen systolic, then the systolic rolling keys are inverted and activated, and the scroll bar will have the systolic data in it. 
     possible modes—systolic, diastolic, pulse, temperature, respiratory. 
     Write_Keys_Data—this routine redraws the rolling keys associated with a certain mode, (example, if the mode is pulse and the user somehow changes the value, this routine draws the 100s value in the leftmost key, the 10s value in the middle key, and the 1s value in the rightmost key): 
     ChangeMode—changes the mode of the screen, this involves (1) turning off the old mode (example—pulse); (2) turning on the rolling keys of the new mode (example—systolic) so now an event may occur—also invert the keys to that they are white on black; and (3) calling Init_scroll_bar to redraw the scroll bar with the new modes details. 
     EnterVitalsDraw—draw the detail on the entire screen 
     (1) write patients name 
     (2) write last date and time that the vitals were entered 
     (3) write the last vitals values 
     (4) turn off all rolling keys 
     (5) change the mode to systolic by calling changemode 
     inc_value—increment the values in the rolling keys, then call Write-Keys_data. 
     inc_temp—same as inc_value, but allow the 100&#39;s key to contain the values 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11. 
     Do_vital_input—THE MAIN ROUTINE 
     (1) calls EnterVitalDraw 
     (2) contains the case statement that handles events. 
     Module 
     graph.c—draws the graph on the screen. 
     make_graph—receives x, y values, x axis label, y axis label, the type of data that the x and y values are (time, short int, int, long int, float, etc.) and draws the graph, depending upon the type of data in x and y, it calls a simple routine that turns the x, y values into x, y plotting points on the screen. 
     Module 
     patinput.c—contains all of the functions used to pick a patient. 
     DoPatientInput—does the entire screens functionality within this one routine. 
     1—init_scroller—passes in the patient list and the two keys (scroller key and scrolling text key). 
     2—handles all events. 
     events 
     in the case that the user picks A-Z, that letter is concatenated onto the search string which is initially empty, then a sequential search upon the text strings is performed to find the first text which is greater in alphabetic value than the search string, then that value is chosen via the function set_scroller_value. 
     in the event the user touches the scroller then 
     get_scroller_value is called. 
     in the event the user touches the scrolling text key, then get_scroll_text value is called. 
     Module 
     vital — 1.c—the starting point of the program contains all function calls. 
     note—Every single “screen” that is called from any other “screen” will be associated by a Calling Identifier (Call ID). 
     DoMainMenu—two main case statement 
     case statement #1 
     handles the events of the main menu, if an event occurs in any of the keys of the main menu, then store the CallID in the variable called ReturnCode. 
     case statement #2 
     while ReturnCode is not equal to 0 loop the case statement. 
     since the ReturnCode is not 0, call the appropriate function associated with the Calling Identifier stored in the variable, the function called will eventually return a code that will again be stored in the variable RetCode. 
     Module 
     scroller.c—contains all functions for the scrolling text windows. 
     functions to be used by other modules 
     init_scroller—initializes all necessary variables and draws of all the detail. 
     get_scroller_value—upon an event in the scroller key, this routine is called and it handles that event, then it returns the value that the scroller is pointing to (in our program, this value is the index into an array of strings—points to the text that was picked). 
     set-scroller_value—the user can set the value any time 
     get scroll_text_value—upon an event in the scroll text window, this routine is called and it handles that event, then it returns the same value as does the get_scroller_value function. 
     functions to be used internally by this module 
     draw_scroller—draws the bar inside of the scroller, then calls draw_scroll_text. 
     draw_scroll-text—draws all of the text that appears in the scrolling text window. 
     invert_picked_text—inverts the text that is being pointed to by the user. 
     Major Functions 
     open_ir—used to initial the IR communication with the AndroDat Card and setup the communication channels with each device. 
     close_ir—used to close all communication channels with the hand held. 
     init_com_info—used to reset and clear all data contained for one specified com)info buffer. This routine is called initially to initialize each buffer and ready to receive data. After a message has been received and put on the process queue, this routine is used to clear the old data and read the input buffer for the next command. 
     collect_messages—this routine will read through each input channel to see if a message exists. If one exists, then the message will be read into a temporary buffer and passed to the routine place message for placement on the input buffer. 
     place_message—this routine will determine if the message being read is the first or subsequent message. If the message is the first packet, then the routine parse_long_hdr is called. If the packet is the second or subsequent message, the routine parse_short_hdr is called. 
     parse_short_hdr—this routine is used to parse the structure tmp_buffer, validate the command being sent along with the correct packet number, then place the data in the appropriate in_buffer message structure. This routine is called after the initial command packet is sent. 
     parse_long_hdr—this routine is used to parse the structure tmp-buffer, validate the command being sent. This routine then initializes the in_buffer structure and finally places the data in the in_buffer messages structure. This routine is called when a handheld device sends its initial packet for requesting a command. 
     comm_server—this routine is the main routine which controls the logic flow of the entry communication server system. 
     process in_buffer—this routine is used to search the in-buffer for completed messages to be placed on the process queue. This routine determines if a message is finished if msg_total=msg_len and msg_total&gt;0. This routine calls ENQUEUE to physically put the message on the process queue. 
     process_cmd—this routine is used to take the next message off the command queue then send it to the correct server for processing. This routine calls the dequeue function to physically dequeue the item off the command queue. 
     process_transmit—this routine is used to take the next message off the transmit queue then send it to the correct server for processing. This routine calls the dequeue function to physically dequeue the item off the transmit queue. 
     packet_msg—this routine is used to physically send the message from the communication server to the handheld computer via the AndroDat Card. It is responsible for all packets of the data and verify of successful transmission. 
     enqueue—this routine takes completed messages and places them on the queue. A parameter is passed to which queue to place the message along with the data to queue. 
     dequeue—this routine will take messages off the queue and place them in a temporary buffer to be processed by the communication server. A parameter is passed to which queue to process along with the temporary space to put message. 
     nulqueue—this routine is used to initialize a queue and prepare it to start receiving data. Call to this routine will destroy any data existing in the queue. 
     com_info—this structure is used to store the incoming message from the handheld 
     in_buffer—this is an array of the structure com_info. This structure is used to hold the individual messages being received from the handheld computers. 
     message_list—this structure is used to serve as the queuing functions for the command processing and data transmission. 
     long_hdr—this is the structure of the header for initial communication to the server. 
     short_hdr—this is the structure for second and subsequent communications of the second command.