Unfortunately, this is now coming to an end. A Linustechtips user reports TI decided to remove support for programs written in ASM or C on the TI-84 Plus CE, TI-84 Plus CE-T and TI-83 Premium CE. This measure was implemented with the release of TI OS 5.5.1 and once it's installed users have no way to roll back to an earlier version.
A key factor that resulted in this move appears to be the publication of a YouTube video from a student, which showed how to bypass Test Mode restriction on a 3-year old version of the operating system. The video received over 250,000 views and it seems TI went into panic mode and decided to take drastic action.
While this move does make the calculator more secure, by preventing future cheating mechanisms, it's also a big punch in the gut for the TI community and a major nuisance for anyone that wants to run advanced programs on the calculators as TI-BASIC and Python are a lot slower:
Performance is bad. It's the slowest Python implementation in a calculator. From TI-Planet's numbers, just about the only calculator that's roughly as slow is a Casio Graph 35+E, a monochrome calculator, and only mostly on integer benchmarks.Hopefully, TI will reconsider.
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Graphics performance in particular is simply atrocious. TI-Planet clocked the put_pixel() fill rate at 48 pixels per seconds. The next two best calculators are 100x to 200x times faster. The next one is 1000x times faster. Forget about gLib, how can anyone be expected to write a simple ray-tracing or fractal script on-calc when it'll take nearly half an hour just to push the pixels out? Even when using TI's proprietary ti_graphics primitives it's still several times slower than the competition's put_pixel().