GP2X Gps In A Gp2x

[Sprite_tm]

Hiya,

I'm the guy who decided to hack a USB port in his GP2X. Some people on this forum were upset about the fact that I didn't post it here. I like this forum, so I decided to redeem myself and post my next project here first. Take a look at http://sprite.student.utwente.nl/~jeroen/projects/gpsgp2x/ ; it's the journal I made while adding a GPS-receiver to my GP2X. Post any questions or comments below, I'll be happy to answer them.

 

[BenScar]

Welcome to the forum, very cool USB and now very VERY nice GPS mod

Makes me want to break out the soldering iron again!

 

[Vimacs]

Nice mod again, like the gp32 gps mod by niglebrown
I dont think anyone was upset, post your thinks wherever you want to it will find its way here sooner or later
Looking forward to your map software!


Did you ever think about installing mods for people on a semi-professional base?
Im sure many people would realy apreciate that and you could make some money with it.

 

[sehs33]

I will never find the courage to do any of your two projects Sprite_tm

Respects and welcome to the community

 

[Loubear]

With this stuff, I don't care where you put it! It kicks ass!

Now only if I added a giant battery pack and a wifi antenna..

 

[aapje89]

Awesome , and as loubear suggested, try putting in a wifi antenna!

 

[___]

i wonder if one could make a decent piggyback unit to store things like additional batteries and hardware... hmm maybe I should attempt to make one with a bob and gps unit ?

 

[Bryanosaurus]

Incredible, I would love to see it finished with program and all. To me, this and that dude's portable BOB keypad would be the two best additions anyone could provide for this unit. Thanks, and keep up the great work

 

[DJWillis]

Very very nice mod

I hooked a serial GPS up to my GP2X via a Prolific PL-2303 USB I/C some time ago and got it going but I just could not see dragging that plus the GP2X plus power about was quite the great outdoor tool it could be .

This modification is much tidier and I may try it when I get my hands on a small enough unit to fit. Fitting an internal GPS in my old GP32 was a worth while hack, not that any usable software was ever done as far as I know. Looking forward to seeing what your software turns into, it's all very promising.

Reminds me, I really should clean up the code I have somewhere that does the NMEA > lat/long conversions and signal cleanup.

How does the GP2X shell and proximity to the GP2X’s PCB effect sat locks, any before and after data?

 

[Feeg]

Fantastic mod. I dug your USB port too.

I've been planning on setting my GP2x up with a GPS receiver, but I didn't even DREAM of fitting it inside.

Inspiring work.

I for one would be very interested in your GPS software once you've got it done.

Huh, I didn't know you were the guy who did the optical mouse scanner hack!

You seem to be single handedly keeping Hackaday interesting to read

 

[dwelch]

I also hooked my gps to my gp2x a while ago. Decoded the nmea strings, drew maps on the screen based on the location. I dont remember exactly if I posted the code but I know I offered it to anyone interested. It was pretty slick, I realized I had maps that were too small in the sense that it was hard to read while driving. So ideally I need to re-do the zoom level. Second to get a usable number of maps I needed a way to automate the "borrowing" of maps. I spent a number of hours on this and then gave up, so basically my project is on hold...It is non-os, meaning no linux, no sdl, no sd card but 64mb of memory minus registers and video and such. Not much to decoding of nmea strings, only one you need bother with intially. Not hard to stay in integer land and avoid floating point.

I found someone selling new receivers on ebay. Bought a receiver, antenna, and some connectors and such from Mouser, all told it was maybe $40 total, probably less. Problem is the connectors were too small for me to manage, tried crimping the wires, dont think I had all of them connected at the same time (although I may have thought I had), and I may have fried the unit, gave up on that. My handheld garmin works just fine though.

If I were to get serious about it (again), I probably would never have thought to mount the gps inside, but would have tried to make an enclosure that mounted to the gp2x, and I would definitely power both the gps and gp2x off the car battery (assuming this is a car naviagion system), and solve that problem.

If you are interested in doing your own mapping software or even nmea on the gp2x I HIGHLY recommend driving around town with a gps in nmea mode feeding something that can log the raw nmea data (like a laptop). then write a windows program (or I can give you one, perhaps already did in this code would have to see) that pushes the logged nmea data out a serial port. The gp2x wont know you are not really driving around town, and you wont need to drive around town to test your software.

Here is my code and binary:
http://www.dwelch.com/gp2x/gcc940-20060725b-gpsplot.zip

I dont know if my code will be much use as an executable. You have to merge it with a number of 600x600 maps borrowed from the same source that I used (not to be named here). The maps are run length encoded, then zlib compressed, a header added, then a bunch put together with a table of contents added, all of this added to the binary and then an .img header put on it so that the ART103 bootloader can run it from an sd card.

It says 940, but that was when I was running on the 940 while linux was on the 920 (ran out of memory for maps fast). The version above is all 920, no linux, no sdl, no sd card (after boot). I made my own gcc to compile it using a modified newlib such that mallocs work (for zlib). This gcc has been posted in another thread...

 

[kevcal]

GPS-mod looks good - if there was mapping software available as well (using readily available maps), that would be excellent
(Not that I'm brave enough to strip the gp2x down yet).

On the USB-mod (hadn't seen this before); why did Sprite_tm add another USB port?
Would it not have been possible just to connect up the power lines on the mini-usb (or add a powered mini-usb port?

 

[Sprite_tm]

Vimax: I haven't seen that gp32 gps mod you mentioned yet. Have an URL? Secondly, I don't think installing mods professionally would be a good thing: as you can see, the whole contraption isn't as sturdy as it could be. For me, that's no problem, I'll just turn on the soldering iron again if anything gets loose, but if I sold the mods, that would be a lot more difficult.

Loubear & Aapje: Tried that, but while there still is enough room inside the GP2X to fit some small things inthere, there's not enough continuous space to fit the antenna, so it'll have to stay external. Too bad, an internal antenna would be great.

dwelch: This isn't a car nav system, it's more like a handy tool for cycling and hiking: instant moving map, speed gauge and tachometer, if the software is done The idea of recording a course and playing it back later is cool to and the GP2X is powerfull enoug to do that: write a small app that records the nmea strings to a file including a timestamp and then, for developement, using a program that plays it back to a fifo and pointing the GPS software to that fifo instead of the serial port. I'll check out your source code, perhaps there are a few tricks inthere that I can borrow.

kevcal: Cause now I can connect stuff like USB-sticks to my GP2X without bringing a BoB or other kind of cable with me If I connected it to the mini-USB-port, aside from technical impossibilities, I'd still need a cable.

 

[kevcal]

kevcal: Cause now I can connect stuff like USB-sticks to my GP2X without bringing a BoB or other kind of cable with me If I connected it to the mini-USB-port, aside from technical impossibilities, I'd still need a cable.

Ah - fair enough - I guess if/when I do such a mod, I'd use a mini and have a convertor cable; just wondered if there was a tech reason :unsure:

 

[Squidge]

it's the journal I made while adding a GPS-receiver to my GP2X. Post any questions or comments below, I'll be

Anyone know if these can be bought in the UK? I've got a couple of spare days coming up and I fancy trying to get something like a GPS module working the GP2X via the SD port.

 

[Vimacs]

Vimax: I haven't seen that gp32 gps mod you mentioned yet. Have an URL? Secondly,

the url was nigelibrown.pwp.blueyonder.co.uk/gp32/hardware/gps/index.htm , however neither archive.org nor google cache grabbed it.

 

[Javacat]

Somebody called Michu posted a few days ago, about having plugged in a GPS device into his GP2X. He mentions something about porting some mapping software to the GP2X when directfb v0.9.26 is released.

 

[dwelch]

dwelch: This isn't a car nav system, it's more like a handy tool for cycling and hiking: instant moving map, speed gauge and tachometer, if the software is done The idea of recording a course and playing it back later is cool to and the GP2X is powerfull enoug to do that: write a small app that records the nmea strings to a file including a timestamp and then, for developement, using a program that plays it back to a fifo and pointing the GPS software to that fifo instead of the serial port. I'll check out your source code, perhaps there are a few tricks inthere that I can borrow.

So more like the pre-map or non-map handheld gps units? That makes life so much easier. I started with a simple bread crumb on a blank screen before street maps. If you want a line on the screen it shouldnt be too hard and maybe you can borrow that from my stuff or maybe my stuff has too much map junk added to see the forest for the trees. The other items like speed, etc, I didnt bother extracting I was interested in road mapping, you will want to look up other items in the nmea data, speed, etc are there, so you wont need to calculate them, just extract them.

It is one thing to develop a program by compiling on a workstation, copying to sd, moving the sd to the gp2x and running it, then returning the sd card to the workstation. It only takes one or two times where the development cycle is, compile on a workstation, copy to sd, move the sd to the gp2x, take the gp2x and gps out to the car, sit in the car for a bit waiting for the gps to lock on, pull out into the street trying to drive with one eye on the road, the other on the gps, only to find that your program isnt working, turn around, go home, go back inside, pull the sd card out and put it back in the workstation, before you realize that one trip around the block logging nmea data, is all you need to save several trips in the car/bike/on foot. The advantage I had by using an external gps is that I could plug the serial cable into the workstation, have the workstation spit out nmea data, the gp2x has no idea that this data is not live and not coming from a gps.
If you have a second gp2x and a bob/serial cable I can get you some nmea data. Actually as you say if you put a fifo or abstraction layer between your nmea parser and the gps (since you cannot remove the gps and replace it with a workstation and serial cable) you could feed it nmea data from within your program for initial development. Hmmm, maybe you could use your usb port and feed the data from a pc to the gp2x across that and bypass the gps for development. Anyway, it saved me tons of time going outside and back in. I may have left some nmea data in my example. gpsdata.txt is what it was called if I remember right.