Performance (On an HP48GX Graphing Calculator) | Hacker News Reader

Performance (On an HP48GX Graphing Calculator)

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36 pointsleansensei18 comments

I never wrote code for the hp48-gx, but I remember that some games written in assembly looked like Game Boy games. The screen even had shades of gray by writing once every 4, 8, ... loop. I don't have the details but it was pretty convincing. Some source code would help in that case.

It was kind of a odd hobby, but there were several game examples

https://www.hpcalc.org/hp48/games/arcade/

Best regards =3

There were even an Zelda attempt with smooth scrolling...

I don't pretend to know anything about HP calc hacking (did a little TI BASIC for fun, that's not even remotely similar). But doesn't this come up in all kinds of daily situations, graphical or otherwise? You only recalculate and update the parts that may have changed. I assume this is similar to why Zelda on my original black and gray GameBoy as a 90s kid was arranged into scenes with few moving elements, so it didn't have to recalculate rendering for the entire screen during action.

The demo video shows full screen scrolling, in which the entire screen updates smoothly.

Also, LCDs require periodic refresh, so partial LCD updates require framebuffer memory somewhere, often in the display controller built into the LCD panel or module, or less commonly into the pixels themselves. It's possible there's a frame buffer hiding somewhere, but plenty of systems don't have one, so the only option is always updating the entire LCD every refresh.

The demo shows deterministic physics with no input, which gives me various suspicions. But I agree, it is clearly updating most or all of the screen for every frame

Ah the Erable HP48G/X. It helped me through AP Calculus BC, SAT-I (math section), and college physics and math for an EE/CS undergrad degree.

I remember using the HP 48's overpowered IR LED and ability to share apps to get the universal remote app to turn on and off TVs in the lecture hall from quite a distance. :@)

Since this is anecdote time: I got an HP49G for the SAT Math subject test (which apparently is no longer a thing). I loved it to bits.

But I ended up putting it away – by the time I was simultaneously doing college statistics, a class on numerical methods and DEs, and few other classes, I got so frustrated with having to remember inscrutable 6-letter softmenu items that I took my first summer paycheck and blew it on a TI-89.

Flashback to lurking around comp.sys.hp48 looking for downloads.

https://groups.google.com/g/comp.sys.hp48/c/BS7c8hRAau0/m/P5...

There was lots of useful software written for it but I was totally blown away by the accuracy of the Phoenix port. Obviously, the graphics couldn't be replicated but even that was well done given the hardware limitations. The game mechanics were pretty close to the original.

I did not have internet access at the time, but it was possible to order contents of this newsgroup on floppy disks from the national HP48 user group, I think they were located at Chalmers university in Sweden. This was my first encounter with the internet, around 91-92-93, browsing Usenet posts from snail-mailed floppy disks.

I wish there was a new generation of HP-48, just with a faster core and better screen. :(

I have a SwissMicro DM-42, which when setup properly is similar to a HP-48, just minus graphing capabilities. Still want a HP-48 refresh.

I want to second all recommendations of SwissMicros. I own DM15L (~$150), DM41X (~$220), and DM42 (~$250), and they are all absolutely excellent specimens. Not a single complaint. They are easily user serviceable, they have a very high build quality and feel like they will last decades (matching modelfkeyboards dot com build quality). The DM42 has a user-enabled N-stack so you can input algebraic expressions of any arbitrary length. The DM15L is an advanced calculator you (or at least I) can grok completely end-to-end, and packs it all into a compact form; I actually prefer to grab the DM15L before the DM42. The DM41X is also an excellent specimen. It includes the ability to {,un}load module files which are dumps of the old HP-41CX module cartridges. I love every single one of them, and cannot shill (for free) SwissMicros enough. You've beheld Swiss watches, now behold a Swiss calculator!

Check my post history, I hate ads. This isn't an ad.

The hp-50g is pretty nice (I know I know, unpopular enter key location), its USB power and SD card make it quite convenient. Of course the screen is the same as before, but the CPU is faster afaik

And then of course there are many HP calculator emulators and others for android

The 50g screen has only slightly (131×80 vs 131×64) higher resolution than the 48G series, but it has vastly better contrast, and, thanks to improved fonts and other UI improvements, the built-in software on the 50g also makes significantly better use of the limited screen real estate.

N.B.: Meta Kernel[1] provides many of the 50g UI improvements on the 48GX — 49g/50g OS is based on Meta Kernel — but installing Meta Kernel in RAM requires a memory expansion card that, at current used prices, costs nearly as much as a used 50g (plus a steady [semi-yearly IIRC] supply of CR2016 coin cells to sustain the RAM card when the calculator is powered off).

While I also prefer the aesthetics and keyboard layout of the 48 series, the 50g with its bundled software suite stands as one of the most hacker-friendly handheld computing devices of all time: while documentation and development tools for the 48 series were widely available, it wasn't until the 49g that self-hosted versions of these tools (System RPL (de)?compiler, Saturn (dis)?assembler, library creation and extraction tools) were bundled with the base OS.

[1] https://www.hpcalc.org/details/213

I'm guessing that you have newRPL. Have you tried putting DB48/DB50n firmware on it? That does have graphics (and RPL). I haven't had time to get familiar with mine, so I can't comment further on capability.

From 2016

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