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                                     v1.0
                 P A R A L L E L   L I N K   I N T E R F A C E
                                     by
                         Ben Eater and George Nachman
themouse@wam.umd.edu                                        ltduck@wam.umd.edu



0.0 KEEPING THE AUTHORS ALIVE

  Send large sums of small unmarked bills. Snapple too (raspberry preferred).

    Ben Eater                   George Nachman
    9404 Five Logs Way          9972 Lake Landing Rd.
    Gaithersburg, MD  20879     Gaithersburg, MD  20879


1.1 COPYRIGHT

  The George 'n' Ben License Agreement ("FRED") permits you to make and use
an unlimited number of copies of any one or more of the George 'n' Ben
software products identified (the "BOB") for your use provided that:

(a) the BOB is not modified in any way and

(b) you maintain the copyright notice on all copies of the BOB.

The BOB is owned by George 'n' Ben and is protected by United States copyright
laws and international treaty provisions.  You may not rent, lease, or sell
the BOB, but you may give away the BOB.

You may not reverse engineer, decompile, disassemble, or annoy the BOB
except to the extent the foregoing restriction is expressly prohibited by
local law.

NO WARRANTIES.  TO THE MAXIMUM EXTENT PERMITTED BY APPLICABLE LAW,
GEORGE 'N' BEN DISCLAIM ALL WARRANTIES, EITHER EXPRESS OR IMPLIED INCLUDING
BUT NOT LIMITED TO IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
PARTICULAR PURPOSE AND NONINFRINGEMENT.  NEITHER GEORGE 'N' BEN NOR THEIR
SUPPLIERS SHALL BE LIABLE FOR ANY DAMAGES WHATSOEVER, INCLUDING DIRECT,
INDIRECT, LOST PROFITS OR INFORMATION, BUSINESS INTERRUPTION, OR OTHER
PECUNIARY LOSS, EVEN IF GEORGE OR BEN HAVE BEEN ADVISED OF THE POSSIBILITY OF
SUCH DAMAGES.  BECAUSE SOME STATES DO NOT ALLOW THE EXCLUSION OR
LIMITATION OF LIABILITY FOR CONSEQUENTIAL OR INCIDENTAL DAMAGES, THE ABOVE
LIMITATION MAY NOT APPLY TO YOU.


1.2 INTERFACE

TI-92 Link requires a parallel interface cable and will not work with a
GraphLink cable. TI's software for the 92 will work with it, should they
ever get around to releasing it. The parallel cable is cheap and easy to
build (Fig 1), if somewhat less compatible with existing software.

-------------------------------------------
 Parallel        TI-Link cable
 (DB25)          (2.5mm 3cond phone)

   2  ĳĿ
   12   red (tip)
   3  ĳĿ
   13   white (ring)

   22   shield (sheath)

The diodes can be any small silicon switching diode.
------------------------------------------- Figure 1


1.3 FILE FORMATS USED

  Because neither of us has any desire to use a Mac, and TI hasn't bothered
with the PC interface yet, we have no idea what the file formats they will
use are like. Instead, we made our own based strongly on the .85G file format
that has some minutely small chance of actually being compatible with TI's
forthcoming file format. Instead of using the file extension .92G, we used
.92@ to prevent ambiguity when TI finally does release their link program.
Hopefully when this happens, we will modify our program to use their file
formats for all of you that want to use the parallel interface.


1.4 WHERE CAN I GET THE SOFTWARE

  You have it. It came with this file. If you cleverly deleted it however,
you can find it at ftp://ftp.digex.net/pub/access/mouse/link92xp.zip



2.1 CONFIGURATION

  The only configuration settings that need to be messed with are the
default data directory and which port your link cable is on. To configure,
select the Configuration option from the main menu. It's obvious.



2.2 SENDING VARIABLES

  Select Send Group File from the main menu. It's obvious. It is not recommended
that you send variables while the calculator is in the home screen because of
reduced performance. We recommend using the var-link screen's receive variable
feature.



2.3 RECEIVING VARIABLES

  Select Receive Group File from the main menu. It's obvious.



2.4 SAVING SCREEN SHOTS

  Select Screen Shots from the main menu. It's obvious.



2.5 QUITTING

  Duh.



3.1 I WANT MORE!

  Check out http://www.wam.umd.edu/~ltduck/ti92.html for TI-92 related
information including source code for communicating with the TI-92.
