faylo

Hello all,

I thought I 'd introduce myself. I am a new owner of a nuvi 855 after previously having owned a gpsv for 7 years. My gpsv is still functional but it was time to step up. Also my technically challenged friend just got a new 1300 and he was rubbing my nose in it. I got tired of the 19MB limit on the gpsv and having to load new maps each time I got ready to travel. Quite often I was not able to fit the required maps for my trip especially if there was more than 1 destination. Now I have the whole U.S. and Canada at my fingertips.

Some of the features that helped me make my decision:
Audio player (I don't have an iPhone or iPod.)
FM transmitter (Music and navigation prompts in my 12 year old truck.)
Voice interface (Very functional given a little learning.)
Linux OS (I like opensource.)

This forum has a lot of valuable information and I thank you all for it. I am mostly a lurker on the various forums I belong to, but I try to contribute if I can without creating clutter.

Thanks again!
-jim

HumVee

Welcome, faylo! I'm glad to learn what you like about your Garmin nüvi 855. It's funny that you bring up its Linux OS...because we just recently had a discussion about which Garmin GPS units run Linux. It appears to be just the 8xx series & the 5xxx series. Aside from supporting open source based products, do you have any plans to hack your n855 to add or change functionality? I know that was a big thing with other Linux based devices (wireless routers. etc.), but I haven't heard of any efforts for the Garmin GPS units running Linux....

faylo

HumVee,

I found that thread and it verified for me that the 8xx series was indeed Linux. Newegg listed it as such but the Garmin site doesn't explicitly mention it in the specs. I also attempted to find if there was any hacking activity going on with the Garmin Linux units and I could find none. But I still hold out hope of coming across something.

I don't have much experience in pc software programming, industrial controls and software, yes, but not languages such as C, C++, JAVA, etc.... However, I have built a couple of Linux servers in recent years and had to make some code mod's to get certain pieces of software working but that was just simple changes to the logic involved and not the modules themselves.

Saying that, I have downloaded the source code but I don't have a Linux machine in a running state in which to do some investigation. It's on my to do list.

I imagine that there may be a way to enable the Blue Tooth functionality on the 855 to make it an 885 or something like that. But I doubt that the internal routing code is open source and the Linux just acts as a container for the proprietary functions of the gps. It is interesting that Garmin isn't producing more Linux gps's, so maybe they are concerned about hacking and thus losing some of their 'secrets'??

If I ever do discover something, I'll post it.
Thanks for the welcome!
-jim

HumVee

Thanks, Jim! It will be interesting to see what happens with these Garmin manufactured Linux devices!

MTalvola

But is the BT hardware, such as the transmitter, physically in the 855?

I also found this quite interesting. Garmin is usually pretty closed minded with regards to ANY outside modifications to OS source code.

How does one go about doing something like this? How would you get the modified code actually into a Garmin Linux unit and execute it?

HumVee

Well...I think that's essentially what a firmware update is - modifying the operating code of a device. So a clever Linux guru (or a team of enthusiasts) would figure out how to write an executable file that would overwrite or heavily modify the existing code on an 8xx or 5xxx. As to the Bluetooth, it's most likely a discrete component on the circuit board - but that wouldn't represent a problem for a programmer, as long as they could figure out the system commands and drivers to get it to function. It'd be no different from what Garmin's OS does now....

MTalvola

That "discrete component" for BT has to actually be there in the first place. But, who knows... Maybe they just crank the same boards out over in Taiwan and only activate certain features via software because the "mass production" aspect is easier/more economical than having separate fabrication lines.

And, now that I think about it, if the Linux devices work like the other Nuvis, it would be simple once you got your code compiled. GUPDATE.gcd is the OS firmware update that gets "installed" whenever a non-Linux Nuvi is updated. The file is simply copied to the Garmin folder in the root directory. It doesn't really get "installed" until the next boot up when you see the progress bar indicating that it's loading. That's the way to get around forced updates with a map update. If you don't want the firmware update, just let it run and "install" everything. When the map update is done and BEFORE disconnecting/turning it off, navigate to the Garmin folder with "My Computer" and delete the GUPDATE.gcd file. Everything will be fine on the next boot up because there will be no update file with a newer date.

Anyways, if the Linux units work the same way, you'd just put the new GUPDATE.gcd file in the Garmin folder and it should auto-install on the next power up.

HumVee

Doh! Sorry, MTalvola...I hadn't pulled up the specs on the nüvi 855 - so I didn't realize you were saying the n855 didn't have Bluetooth capabilities. This discussion brings up a very good point. It's quite possible that it's cheaper for a manufacturer to build boards that are all the same in a product line, but then disable components in some models to differentiate from their higher product lines. It all depends on how expensive the discrete components are - and whether or not a manufacturer doesn't slag the components with a laser on the models that are sold without the feature....

MTalvola

I've heard of people being able to gain features with software tweaks. I remember reading about a certain (Tom Tom ?) model could use TTS voices because the speech synthesizer hardware was the same as higher end units, but the OS didn't support TTS voices...

faylo

From the diagnostics Inventory screen I can see something called "Parrot Bluetooth Software". As to whether or not this is both transmit/receive or receive only, I don't know. Bluetooth spec is not something I am familiar with, but could probably find out with a little research. I am pretty sure the voice activation function is Bluetooth, but it may only be one way. Also, the source code doesn't refer to the various models of the 8xx series, only the entire series. Possibly, when the unit boots up, the OS examines the model number somehow and then enables the appropriate modules. Also, I wouldn't be surprised that the internals of the 8xx series are the same to cut down on manufacturing/support costs.


Since the OS is Linux, it should support various communications methods, such as SSH (Secure Shell), FTP (File Transfer), HTTP, Telnet, or others.... Any of those could allow access to the OS and thus the ability to change it. However, there may be authentication required also and that would have to be cracked, if possible. Examining the source code may provide the answer to all of this. Or may not if security is involved.

Another thing to keep in mind, if the OS is changed, the checksum will also be changed and you may not be able to update maps or be required to reinstall the latest firmware. Just like what is going on with the iPhone and the "jail break" hacks. Once the phone is broken, it is frozen at that level of firmware and if an update is installed, the security measures are back in full force and a new hack would have to be developed.

faylo

After reading the messages that came in while I was writing the above, I see that the 855 has a directory E:\Garmin\Update and this has a 67MB file with a ".update" extension and 2 other files that contain the product key. It seems that this ".update" file is similar to the "GUPDATE.gcd" file MTalvola refers to. Looking at this file in notepad shows it to be compiled file of some sort.

I wonder what the source looks like? I can't find the original download of the update, so it probably deletes itself once the update is complete. Maybe I'll download it again and see if it can be opened. I seem to remember it was an executable zip.

It occurs to me that maybe there is no way to communicate directly with the OS on the machine?

HumVee

Since the GPS device has no Ethernet port or 802.11 WiFi capabilities, using SSH or other protocols seems unlikely to work. All you have is a serial connection via USB. I figure that someone would have to figure out how to compile their own firmware update, and then apply it to the device, just like what an official Garmin update does....

MTalvola

For the non-Linux Nuvis, it's a simple "drag and drop" of the new file to the Garmin folder. It does some date/checksum comparison of that file to the one in the "deep memory" we can't access. If it's newer, it gets installed on the next power up. If that file has the same checksum or is non-existent (as in my "not do an update" map update post), then it boots as normally. If it's older, on startup it will prompt you that you are trying to install an older version of firmware than what's currently on the unit. That's how people can backdate their firmware if the new one they installed causes even more problems. But, that never happens, right?

faylo

Yes. I agree.

vs2

Hi. New here and I have a Nuvifone G60 that was locked to AT&T which I eventually got unlocked through Garmin (long story) This thread interested me as I have been searching for an answer everywhere.

In short iam from NZ and are trying to update my software to the APAC version (currently I have the AT&T version) These phones are all the same in functionality but there are 5 different software versions (AT&T, APAC, Atlantic,Czech Rep/Poland and Sunrise.)

As you can see from this page Linux is also on the Nuvi 5xx, 8xx and 9xx:

Linux Source Code - Garmin Developer


I have downloaded the APAC software 2.43 (from Garminasus) which is an .exe with builtin webupdater but it would not update. I have tried modifing the garmindevice.xml but still no luck. When the .exe is run is puts these two files into an 'update' folder on the device:
B103200.UPDATE (103MB) and
modem-2.26_1-8-21-EU.bin (18MB)

For a test I downloaded the latest software for the Nuvi 855 and it also extracted to the same folder as a .UPDATE and not .GCD

I understand there is risk here but can anyone tell me how to force this update as for some reason the device just will not recognize the update. Should these two files be left in the update folder or put on the SD card? Should B103200.UPDATE be renamed with a different extension.

So I would like to update from ATT software to APAC. Do you think it is possible?

My reason is is that the APAC version is 1. unlocked and 2. Many better features that are not available with the AT&T version.

You can use the G60 as a Navigation device by simply putting an old ATT sim card in but then the phone is unusuable until you get a NCK code to unlock it for worldwide usage.

In the APAC update there is a phone .bin (ROM) which is a ------.EU.bin where as the ATT version has the ---.US.bin.

Thanks very much.