[5.4] Try Var-Link To Fix Graphlink Transmission Errors; [5.6] Build Your Own Graphlink Cable (Hess's Bcc Serial Link) - Texas Instruments TI-89 Tip List

To be completely safe, use the procedure in tip [5.2] to transfer your data and programs from your
HW1 calculator to the HW2 calculator. In general this means transferring programs and variables
individually with GraphLink, then restoring them individually to the HW2 calculator.
(Credit to Lars Frederiksen)

[5.4] Try Var-Link to fix GraphLink transmission errors

Some ASM programs may crash your calculator, requiring that the batteries be removed. In some
cases, GraphLink will not work after this crash. Entering, then exiting the Var-Link screen seems to fix
this problem, 100% of the time, according to ZLX. He is using a TI89, AMS 2.05, HW1 and GraphLink
2.0.
(Credit to ZLX)
[5.5] Use TalkTI to develop PC applications which communicate with the 89/92+
TalkTI is a set of software components which implement data communcations between a personal
computer and TI calculators, or the CBL/CBR. TalkTI only works with Windows operating systems. The
TalkTI components can be used with scripting languages such as VBscript or Javascript), or
programming languages which are compatible with the Microsoft COM, such as Visual Basic, Visual
C++ or Visual J++. The documentation includes examples for these languages. The details of the
communications protocol and format are hidden by the software components. TalkTI works with both
the gray and black GraphLink cables.
The TalkTI SDK can be downloaded here:
http://education.ti.com/developer/talkti/high/hilight.html
TI hosts a related discussion group:
http://www-s.ti.com/cgi-bin/discuss/sdbmessage.cgi?databasetoopen=calculators&topicarea=
Software+Development+Kit+for+TalkTI&do_2=1

[5.6] Build your own GraphLink cable (Hess's BCC Serial Link)

A GraphLink cable provides a serial interface between the calculator and a personal computer. This
gives you the capability to download programs to the calculator, to back up your calculator's memory
on the PC, and to transfer variables between the calculator and the computer. The original TI cable
was gray in color, and so was called the gray cable. TI has since released another version, called the
'black cable', which is less expensive, has a higher transfer rate, and seems to be more reliable. The
black cable is reasonably priced at $20US, and is readily available, at least in the US.
Even so, there are some good reasons to build your own cable. One reason is education: to learn how
such a cable works, and to gain insight into the GraphLink communications protocol. If you live outside
the US, TI's cable may not be as readily available, or the cost may be excessive. Finally, if you are an
electronic experimenter, you probably already have all the parts you need to build the cable.
Several users have developed alternatives to TI's GraphLink cables. As an example, I have chosen a
design by Frank Mori Hess, for several reasons. Frank calls his design the BCC, which is an acronym
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