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

29 pointsby JPLeRouzictoday at 5:43 AM6 commentsview on HN

Comments

SillyUsernametoday at 7:46 AM

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 ;)

guentherttoday at 8:00 AM

"real-time GPS-driven moving map display"

Not the IMHO more interesting analog tech which lifts signals out of thermal noise.

svagtoday at 7:30 AM

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/

JPLeRouzictoday at 5:48 AM

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.

ErroneousBoshtoday at 8:15 AM

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 ;-)

orielhaimtoday at 8:34 AM

[dead]

razashaikh92today at 6:37 AM

Cool software keep it up