alt Hacker NewsFrom here: https://www.cemetech.net/news/2026/4/1062/_/ti-84-evo-calcul...
> 3x Processing Power - Matching one of the speculated options, the calculator appears to use an ARM Cortex CPU, finally retiring the z80 and ez80 family of CPUs that were used in three decades of TI-83 and TI-84 Plus graphing calculators. It's running at 156MHz, compared to the 48MHz of the older calculators. It appears likely that in an unexpected break from over 30 years of TI's operating system codebase, the OS has been re-implemented with new features natively on the ARM CPU rather than using an ez80 emulator to run an updated form of the TI-84 Plus CE operating system.
It looks like TI is finally moving away from the Z80. This must have been a pretty big engineering effort on TI's part. Like the article says, up to this point all of TI's low-end graphing calculators have been Z80 based and use the same system software that has a lineage dating back to the early 1990s. They were previously so wedded to the Z80 that when they introduced Python programming to their calculators, they did so by adding an ARM microcontroller that runs MicroPython, while the main eZ80 CPU acts as a serial terminal.
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Fun memory trip. Learned assembly on those old Z80s in middle school. I had to go re-dig up SafeGuard, a program I made by reverse engineering TI's TestGuard, to stop admins from wiping your calculator memory and all your games! https://mikeknoop.com/upload/safeguard/
Does this mean uncle worm won’t run on it out of the box? A tragedy
>cemetech
>Kerm Martian
There's some names I haven't heard in a while :)
Real shame since cortex has a admin TrustZone processor that is licensed to special interests only. For the educational market, this "security" is a selling point. It guarantees that a student isn't running unauthorized code or "cheating" apps. It also likely allows OTA auditing of the classroom's state.
Much nostalgia. The TI-83 Z80 was how I learned assembly as a teenager, so I could write better calculator games than was possible with TI Basic. Many others here had a similar experience, I’m sure. It’s been a couple decades, but I’m sure I’d still remember most of it if you put me down in front of a bunch of Z80 asm code.
One thing that I remember vividly was you had no MUL or DIV, so you have to implement them yourself with shifts, adds, subtraction, etc. This was an extremely useful learning experience