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I bought an HP48 in 1990 junior year in college when it came out. A calculator WAS required for engineering school, but this one made everything way easier. I t

I bought an HP48 in 1990 junior year in college when it came out. A calculator WAS required for engineering school, but this one made everything way easier. I think it was almost $200. Anyway, once you go RPN, you don't go back. It makes way more sense. It finally died 5 years ago: the keys stopped working. I read about how to repair the keypad but finally had to let go. I had all my crib sheets from engineering school stuffed into the pouch. That calculator was epic. I can't imagine trying to do complex math with a slide rule, even though that's how engineers had done it for ages.

lloeki 6y ago
Similar story. Got a 48GX in high school. Everyone had TI89, maybe TI-92. I was the only one with HP. Even with its lowly Saturn CPU and perceptually slower, it was trouncing the TIs at basically every task, especially when you customised it. I learned RPN and RPL alright, but also got to dive into System RPL: the low level, faster, much more rich RPL, but where every argument was basically unchecked as it was more like HP-provided ASM routines in disguise. And then learned to bit-bang stuff on the screen in assembly with all the timing tricks to produce 4 grayscale instead of just black/white. Great for coding small games. Got the the third party CAS algebra extension card that also replaced the original UI for the same thing, only faster and better, and with a much more potent symbolic solver, whose UI was absolutely glorious to write, select, navigate, and perform advanced stuff. Also got a maxed out storage expansion for the second slot. Such storage was not solid state so it required a continuously operating CR2032 battery to persist over time. Unfortunately, as robust as it was, some time after engineering school it took a hard fall too much and was irreparably broken. Later got my hand on a HP49G+, ARM powered but surprisingly the default was to run an emulation of the Saturn CPU, and CAS was bundled. You could still code for the ARM one though. By that time I lost interest so it currently sits in a drawer. Also preferred the 48 boxy design, especially the mushy keys of the new one were way worse.

lloeki 6y ago

Similar story. Got a 48GX in high school. Everyone had TI89, maybe TI-92. I was the only one with HP. Even with its lowly Saturn CPU and perceptually slower, it was trouncing the TIs at basically every task, especially when you customised it. I learned RPN and RPL alright, but also got to dive into System RPL: the low level, faster, much more rich RPL, but where every argument was basically unchecked as it was more like HP-provided ASM routines in disguise. And then learned to bit-bang stuff on the screen in assembly with all the timing tricks to produce 4 grayscale instead of just black/white. Great for coding small games. Got the the third party CAS algebra extension card that also replaced the original UI for the same thing, only faster and better, and with a much more potent symbolic solver, whose UI was absolutely glorious to write, select, navigate, and perform advanced stuff. Also got a maxed out storage expansion for the second slot. Such storage was not solid state so it required a continuously operating CR2032 battery to persist over time. Unfortunately, as robust as it was, some time after engineering school it took a hard fall too much and was irreparably broken. Later got my hand on a HP49G+, ARM powered but surprisingly the default was to run an emulation of the Saturn CPU, and CAS was bundled. You could still code for the ARM one though. By that time I lost interest so it currently sits in a drawer. Also preferred the 48 boxy design, especially the mushy keys of the new one were way worse.