A software thing I built: GPS on a 25MHz 486-SX

JPLeRouzic

The author says: " It used Voronoi Cells and reduced most math to 8- and 16-bit integer calculations with one or two single-precision floating-point calculations. " I wonder if it can be used to speed up LLM inference.

svag

I believe the library mentioned in the article should be this one https://geodyssey.github.io/overview/overview.html and here https://www.lukatela.com/geodyssey/

SillyUsername

I built one, tracking fleet vehicles with a custom box, using tiled maps, on behalf of Vodafone, back in 2002. I still remember I wrote a basic trans-mercator library too! Of course Mercator projection may go out of fashion soon https://www.independent.co.uk/news/world/africa/world-map-eq... :) Hope I'm called back to update the library ;)

guenthert

"real-time GPS-driven moving map display" Not the IMHO more interesting analog tech which lifts signals out of thermal noise.

ErroneousBosh

One of the things I discovered a while back is that even fairly crude trig approximations don't put that much error into your position, over a small enough distance. To calculate things like straight-line range from where you are now to where you need to put a unit for an emergency, you're probably not working over an area of more than a couple of hundred kilometres radius and the error will be within a few dozen metres. And once you get within about half a k, you're driving towards the column of smoke anyway ;-)

contingencies

In Y2K I built a Linux on PC104 solution with GPS, bonded dual-channel mobile 9600 baud data links, and a (slow) image feed. It was kind of special to see the data coming over the mobile network in those days: this was before mobile data using basic PSTN modem tech! Very lossy and slow, as the algorithms did not account for mobile voice compression.

tomaskafka

A bit related - I tried if I can push Fable to write a Garmin map renderer that would be comparably fast (or faster) on Fenix 8 than the one they claim is possible on Fenix 9 only. I think I got very close, rendering detailed topographical vector map at over 15 fps on QEMU simulated single core simple CPU comparable to actual Fenix 8. https://www.reddit.com/r/Garmin/comments/1vzaz4w/we_live_in_...

AshamedCaptain

I once worked on a handheld garmin gps that used a 386 ... not sure if it ever became a product, though. It definitely had moving map... 1MB of it.

fegu

Oh how I have fond memories of Dr.Dobb's journal.