And you? When will you begin that long journey into yourself? Rumi
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Texas Instruments cryptographic keys Texas Instruments uses a series of RSA cryptographic keys in their line of graphing calculators to digitally sign Flash applications and operating system upgrades. This is necessary to transfer and store first- and third-party Flash applications and operating systems on these calculators. TI has kept nearly all of these keys a secret to prevent us from using our calculators the way we want to use them, but we have recently discovered what they are and have begun using them to create viable replacements for TI's OS (or AMS, if you have a 68k model) as well as Flash applications for every model from the TI-73/Explorer to the Voyage 200. As a user, these keys are not very important, but for developers, these are an important step in distributing your application or OS. I have included the raw key information, the .key files for use with signing utilities, and instructions on how to use them. Hopefully this helps someone out there.
.key signing files A zip file containing all the .key files you would need for a signing utility (such as RabbitSign, Build8XU, or resign68k) is here.
how to use .key files To sign a Flash application or operating system upgrade, you need two things: A signing utility (such as RabbitSign, Build8XU, or resign68k The appropriate key file The key file you use is determined by the key ID. Each model and key type has its own key ID as above. For example, if you want to sign a Flash application for the TI-89 Titanium, use the 0109 key. If you are re-signing an existing Flash application or OS upgrade, you may need to check the OS header to determine which key to use. As an example, suppose there is an 89Ti Flash application you want to re-sign. Because the TI-89 Titanium can accept both 89-signed and 89Tisigned Flash applications, there's no way to know which key it was signed with unless you check the OS header. If you open the 89K file with a hex editor, you'll see the application header at the beginning. Field 8010h or 8110h will contain the key ID. In this case, it would be either 0103 or 0109. The readme for each signing utility can provide more details.