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Like I said over in the Mimas thread, I've been experimenting a bit to see how practical it would be to sign apps on the calculator. So I figured I'd take a look at how Axe generates applications.(App signing on the calc is never going to be instantaneous (except maybe on the Nspire in ARM mode), so you probably don't want to do it every time you build an app, but it would be nice to have it as an option when you want to distribute your app to others.)Thus, a few points:1. It seems that when Axe generates an app, the "signature" is filled with zeroes. Why?! Why couldn't you use FFs? Don't you realize how much harder that makes it? 2. App signatures on the 83+ must begin with the bytes 02 2D 40 (followed by 66 bytes of data), not 02 0D (the latter is used for OS signatures as well as for app signatures on the 89/92+.)3. Does Axe deal with the 55-mod-64 bug? (An application must not be exactly 55 bytes long mod 64; if it is, it can't be installed on a TI-73 or 83+ BE due to a bug in the boot code. So if an app is 55 bytes mod 64, RabbitSign will add an extra byte to the end, and increase the app length field accordingly. This would be easy to do at the time the app is compiled, and hard to do later.)4. Only tangentially related to app signing, but does Axe deal with the FF-at-the-start-of-a-page bug? (If you have FF at the beginning of any app page, the OS will set the entire page to FFs when apps get defragmented. I wrote a program to patch the OS and fix this bug, but it's best to avoid that if at all possible.)
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