Urgent: Chance To Implement Gps&wifi Via Usb/sdio?

[klakklak]

hey folks,

hopefully this is the right place to post my question... I am rather confused at the moment with all the shortcuts (gp32, gp2x etc.) and really hope to find some people to answer me my simple (?) question!

Here it comes:

Would be possible to upgrade a GP2X handheld with a SD-CARD (SDIO) wifi adapter and a GPS USB adapter (via usb port ) and get to run it on Linux?


The question is very important to me since I am a graduate assistant at the university of art, braunschweig germany and we are looking for a good platform to use in our coming game-project. I know the GP32 and hoped the use of GPS/WIFI would be easier with the GP2X, but I read a little and there should be a theoritical chance, right?

Any help would be great, and detailled information of how-to is always welcome.

Greetings from Germany,

Arjan

P.S.: Of course I will tell you more about our project if everything works out, if you like.

 

[Vimacs]

there is no proper sdio driver yet so you would have to write oen, but hardware wise its possible, but usb would be a cheap and maybe easier aproch, however usb host isnt totaly worked out yet.

Best would be to wait some weeks/months and look at what state it is than.

 

[klakklak]

thanks for your reply vimacs,

sounds not bad...

so you mean it would be also possible to have both adapters (wifi and gps) running via the USB port? that means GP2X allows something like a usb-hub (->different signals to one single usb port)?

sorry, my technical knowledge as you can see is not the best.

greetings
arjan

 

[Tobriand]

Only thing is you would not be able, iirc, to use the built in USB port, since that doesn't have host. GPH decided to use a separate USB 2.0 slave-only chip to speed up data transfer, since they considered host unimportant.

However, the USB 1.1 unpowered host in the MMSP2 chip (the CPU) is, I seem to recall, exposed on the EXT socket. So at some point, with any luck, it'll become possible to plug a USB adapter into there and get at least unpowered host USB - which might well do you, depending on the hardware you're using.

Bear in mind though that I am *not* involved in either software or hardware development, so there's a good chance I'm only part of the way there in terms of what the situation is...

 

[klakklak]

thanks tobriand,

hhm so no easy usb host use... well, I would prefer SD-Slot plus one USB adapter anyway because of space. a card to put into a slot would always be nicer, of course.

Unfortunatly we need both technologies (GPS and WIFI) at the same time, so we must find some way to attach them both.

By the way, could an existent Linux GPD-tool be used to read the GPS informations? would it be that easy to access data?


thanks for your help
arjan

 

[Squidge]

Personally, for GPS usage I would source a GPS which uses a standard serial port (RS232) and then with some simple electronics (eg. MAX232) you could attach it to the ext port very easily and communicate with that without any of the problems or issues with USB host. No drivers would be required for this as it's all standard stuff. All you would have to do is parse the NMEA data, which is pretty much childs play.

Wifi on the other hand is a totally different ball game, and it is this one which I'd suggest to run over USB host, and it'll be far easier than attempting to get a SDIO version to work. USB Wifi is pretty much a standard and there is lots of documentation and source code around. For SDIO Wifi however, there's no documentation or source code unless your prepared to sign up to the SD organisation, sign NDA's, pay $$$$ (don't expect much change from about ten thousand), etc.

 

[klakklak]

@squidge
thanks a lot for your ideas, sure you are right that GPS via serial port would then be a lot easier. great!

about Wifi via USB, what do you think about what Tobriand said earlier about GP2X' USB port? as I understood, it wouldnt be possible to use a commercial cheap Wifi usb stick with the Mini-USB port? (I guess you guess would use that if it'd be possible)... even if the wifi stick is passive usb?

So there wouldn't be the need to use the EXT socket as Tobriand suggested? Because that would be used by GPS now.


Thanks a lot again guys, you really help me (us) a lot to gather information quickly. Hopefully we can use the great GP2X for our project.

Arjan

 

[Squidge]

The mini-usb socket is connected to a PLX Netchip 2272, so it doesn't support host functionality. So yes, you would have to use the ext port for both devices. It shouldnt be problem though; if you've got to create a PCB for the MAX232 to sit on, just add a usb receptacle too.

Just think how tidy your solution will be

 

[nickspoon]

Getting a PDA would be easier (and possibly cheaper), but good luck with the WiFi/GPS implementation, and if you get it working, I'll buy one!

Wasn't there talk of a breakout box of some sort? Either that, or you find a device that does both GPS and WiFi by RS232 (hard to come by I expect) and stick an EXT port thing on the end.

 

[Shikaku]

How fast is the EXT port? Why aren't there people wanting to use that for Wi-Fi? Too slow? Output only?

 

[nickspoon]

How fast is the EXT port? Why aren't there people wanting to use that for Wi-Fi? Too slow? Output only?

Lack of either documentation or effort, I think it's the latter.

The source would probably help too, but I don't want to bring that up again, so pretend I never said it.

 

[Squidge]

EXT USB is 1MB/sec - perfectly fast enough for Wifi, but the RS232 will probably struggle over 30KB/sec or so, specially over a long cable.

 

[Klepto]

I'm not a hardware guy so I don't know, but is this any use? USB 1.1 is nowhere near as good as 2, it seems GPH missed a good opportunity when they decided that host functionality was unimportant.

The idea has crossed my mind that perhaps they deliberatly don't want to include stuff like that (touchscreen too) to avoid getting into competition with mainstream PDAs like the Zaurus.

 

[klakklak]

@nickspoon
yeah, a pocketpc or palm would be cheaper, but what we want to do is augment an existing game (basically) and most of the open-source ppc games lack of complexity in terms of aesthetics and game rules.

with the GP2X i thought we would have the chance to run any (small) linux game, there are more interesting games to work with. in any case, our project is a research project, so it wont be a commercial product and thus wont be about cool graphics and playabilty... but you know how it is... you always look for the nicest look&feel, and the GP2X has it all.

if we would spend more time on making the project possible hardware-wise, then I see no big chance in developing on the GP2X.

@all
well maybe I just should to the real tech-people do the hardware-research, but university communication is slow

how much time would you think would it possibly take a bunch of pro computer-science students who gather once a week for some hours? is it possible in a couple of months?

 

[dioxide]

Ill use this thread to ask a question that does not concern the main topic of this thread. Would it be possible to add a 3D accelerator(some sort of self-powered one) through either the EXT, USB, or SDIO?

 

[BradN]

dioxide: Is it possible? Probably. While still displaying on the GP2X's screen? not likely. At 30FPS, it would have to transfer 4.6 megs a second plus any 3d command overhead, and the only thing with enough bandwidth for that is the USB2 interface (maybe SDIO, but I don't think you'll ever see a 3d accelerator made for it), and the USB2 only supports client mode...

The way I could see it being done, is by connecting it with a full fledged linux box with 3d acceleration, and running an X/OpenGL game on the GP2X, and sending the X connection to the other machine with ethernet-over-USB. But at this point, you're more or less playing the game on the big computer, but using the GP2X for the game processing, which is kinda useless.

 

[Winterkid]

WARNING: The following is based on what I know of the ARM Dual-core and peripheral devices in general.

Ummm.... the EXT port is fast, but the ARM CPU(s) would have to shunt all 3D operations to the EXT port and switch control of the LCD to the external chip, and the external chip's memory. If anything, I beleive it might slow down the whole process, even more than just writing code to make the second CPU act as the video processor.
For really advanced and very complicated 3D intensive apps and games, it might make a slight difference in quality, but for speed, I would highly doubt it.

 

[OmarNawaz]

How hard will it be to implemet mass storage drivers over the ext port?

i dont plan on using it from the firmware or anything till the source is released.

just want to attach a usb drive and see what happens.