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                       Mass Storage Utilities for the HP-41
                               Quick Reference Guide

            The Mass Storage Utility Programs will allow you to store
            and retrieve information conveniently by way of the HP-IL
            loop, overcoming certain limitations of the HP82160A HP-IL
            Interface. 

            If you want to get the best possible performance out of your
            HP-IL periherals, you should only hook-up the peripheral(s)
            that are specifically required to do any given task.  The
            Utility Programs will provide trouble free service when used
            with only one mass storage device, one printer and one
            display device. 

            If you connect additional HP-IL printer or display devices,
            program output could be sent to the "wrong" output device. 
            
            If you have more than one drive connected to the loop, you
            should remain in the Manual Mode (Flag 32 Set).  This is
            done by executing the MANIO function.  Remove the mass
            storage media from all mass storage devices except the
            primary device, before you use programs such as "NEWMED" or
            "WRTP" to store information onto mass storage media.  This
            will help protect your valuable files. 
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            If you have more than one drive connected to the loop, you
            must also make one drive the primary device with the
            SELECT function.  See the Owner's Manual for the HP82160A
            HP-IL Module, pages 46 to 49. 

            Part I -- Using the full capacity of your HP-IL disc drive

            A.  Allocating Directory Space
            If you wish to allocate directory space for more than 447
            files, use the following procedure: 
               1.  Copy the "NEWMED" program into the HP-41. 
               2.  Initialize the medium with NEWM. 
               3.  Enter the number of files for which you wish to
                   reserve directory space into register X. 
               4.  Execute the "NEWMED" program. 
               5.  Repeat steps 2-4 to initialize other storage media,
                   as required. 
               6.  Recover the space used by "NEWMED" with the CLP
                   function. 

            B.  Using The Full Capacity Of Your Disc Drive
            The "Write" program ("WRTP", "CREATE", "WRTS", "WRTK" &
            "WRTA") allow you to use the full storage capacity of your
            disc drive.  It is NOT needed with the HP82161A cassette
            drive.  This utility program was designed to be transparent
            to the user.  Once you have copied the program into your
            HP-41, you can use the "WRTP", "CREATE", ect.  programs
            just as you would use the WRTP or CREATE functions
            provided by the HP82160A Interface module.  However, the
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            utility does not implement the automatic "Housekeeping"
            which allows you to use multiple cassette drives as a single
            unit in the AUTOIO mode. 

            Therefore, if you have more than one disc drive on the loop,
            execute the MANIO function, remove the storage media from
            all the drives except the one upon which you want to store
            information, and SELECT the target drive as the Primary
            device. 

            Once this is done,you are ready to use "WRTP", "CREATE"
            or any other function that creates a new file on your mass
            storage medium. 

            The Utility program will allow you to "CREATE" data file
            with more than 20000 data registers, provided you have
            enough unused disc space. 

            Before you can use SAVEAS, you may have to execute 0,
            SEEKR. 

            Part II -- Rapid Access To HP-41 Files

            You can use either "SRCHX" or "GDIRX" to by-pass the
            time consuming directory search.  Use the following
            procedure: 
               1.  Copy "SRCHX" or "GDIRX" into your HP-41. 
               2.  If you have more than one mass storage unit in the
                   loop, execute MANIO.  Use the SELECT function to
                   make the drive that has the desired file the Primary
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                   device.  Since the programs provided in Part II of
                   the Utility do not store information onto mass
                   storage, you need not take any other precautions. 
               3.  To obtain access to the n th file on the medium,
                   enter the file name into the ALPHA register, then
                   enter n into register X, and execute either SRCHX
                   or GDIRX. 
               4.  If you do not know what value of n you should use,
                   you can use the function DIR to produce a listing
                   of all the files available.  You can then count
                   the number of files from the start of the directory. 
                   However, this is both time consuming, and prone to
                   error. 
               5.  The easy solution is to use a reference listing that
                   numbers the files for you.  This is easily done with
                   the DIRL or DIRLX program.  See below. 

            Getting a numbered file listing:
               1.  Copy the "DIRLX" program into your HP-41. 
               2.  If there is more than one drive on the loop, execute
                   MANIO, and SELECT the desired drive as the
                   primary device. 
               3.  Execute "DIRL". 

            Updating numbered file listings:
            If you have added a few files, and only want to get a
            listing of the files begining with file n, do step 1 to 2
            above.  Instead of executing "DIRL": 
               3'.  Enter n into register X. 
               4'.  Execute "DIRLX". 
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