acer a0a 150 - Built in GPS

Hi,

Not sure if this of interest to anyone (I may well be an idiot), but the story goes like this...

I bought an Acer A0A 150 with the built in 3G networking (powered by a Globetrotter GTM380 module).

The plan was to use it as a computer, and a GPS system, so I went out and bought a bluetooth dongle and a bluetooth GPS unit.

Anyway, I was tinkering around with the computer, and looking up some of the components on the internet, when I found on Option's website (the manufacturer of the OEM GTM380 module) that their 3G module actually already has GPS.

This GPS feature was not listed anywhere in the documentation, and in fact, does not work out of the box as it seems to have been factory deactivated for a reason.

I finally got the module to fire up using AT commands of all things to the COM port of the GTM380 module. The way I got it up and running is as follows:

1. Install the latest version of Globetrotter connect from Option's website, www.option.com
2. Connect to the Application Interface COM port of the GTM380 using Hyperterminal (the COM port on mine was COM3, but might be different on different systems, it can be checked by going to Device Manager and checking under Ports, there will be one there labelled application interface). As GlobeTrotter Connect uses the same com port, it must be shut down before connecting.
3.Type in ATE (which lets you see what you are typing) and press enter
4.Type in AT_OIFC=? (this shows you various com port options)
5.Following the options given, if you want the modem port activated, the application port activated, the diagnostic port activated and the GPS port activated (along with a secondary application port, which is handy, because then you don't need to disconnect from Globetrotter to talk to the module with hyperterminal) you type AT_OIFC=2,1,1,5 and hit enter.
6.Now type AT_ORESET to restart the module.

The connection in Hyperterminal will drop, and then a few seconds later some new devices should start installing, namely a GPS interface and a second application interface.

But even then the GPS is not active.

Go back to device manager and check the numbers of the new ports, on my system GPS was COM14, and the secondary application port was COM16.

You can restart Globetrotter now, and use hyperterminal to connect to the secondary application port, in my case COM14.

Now type AT_OGPS=2 to start GPS tracking. The GPS data starts streaming out of the GPS Comport, in my case 14, and as soon as it gets a satellite fix it starts tracking.

The question is, is this something that everyone knew about? Because I had no idea that this laptop had inbuilt GPS and it was nowhere in the documentation. Sorry if I am reinventing the wheel here, but I googled the hell out of this trying to find out how to turn this modules GPS on and found nothing, so hopefully someone finds the above useful.

 

Someone posted today on this site requesting if the GTM380 could be used for GPS, so you answered that question.

Yes, there has been some discussion lately on this site about using the Sierra Wireless MC8781 3G card with upgraded firmware for the GPS function. I can atest that the MC8781 works fine for GPS and required no Hyperterminal use. It is nice to not have to install a GPS receiver on the AAO.

 

Okay, I just got an AAO 150 and I'm trying to figure out if it has GPS built in or not. I'm not a techie, so is there an easy way to find out if it is upgradeable/modable to get it to work as a gps unit.
I would wet myself if it could..... :lol:

 

Hi acutturi.

The first thing you should check is whether your netbook has a 3G module. Easiest way to tell is to look at the bottom right hand corner, to the right of the trackpad. There is a picture there of a little satellite dish which is your wireless on indicator, if there is also a 3G logo, I assume the netbook also has 3G.

If it has 3G, then you need to know what type. Go to Control Panel, and then to System, then to the Hardware tab, and then to Device Manager. Click on Network Controllers. If one of the controllers listed there is the Globetrotter Module HSxPA then you are in luck, and your netbook should be able to do GPS. Otherwise, probably not.

 

Excellent work there sir! It makes me even more keen to modify my Acer to allow it to take one of Option's wireless modems.

The 'hidden' GPS is quite an interesting issue. Module manufacturers have been increasingly keen to include multiple RF functionality in their products. To provide 'catch-all' solutions that are likely to fulfil the needs of a wider variety of OEMs. This reduces the number of different models they need to make, so increasing the volume (and decreasing the price) of the ones they do make.

GPS is becoming a natural complementary feature to include in wireless modem modules. Most of these GPS chips actually being (appropriately) A-GPS - the wireless network-enhanced variant of GPS. So the GPS functionality exists in the module and it's up to indiviudal OEMs to choose to use it or not. Some OEMs may end up with chipset functionality that they don't even want simply becasue its there by default! So it's Is better to think of the GPS as being dormant rather than hidden.

The future trend will be to go a step further in integration - and have multiple RF functionality on a single die (chip). We won't need modules any more (which are comprised of separate components). Qualcomm's Snapdragon chip is a HSPA, EV-DO, A-GPS, 1Ghz CPU, 600Mhz application processor, Bluetooth and Wi-Fi all in one! Should make for some interesting devices!

http://encoreppc.files.wordpress.com/20 ... ual280.jpg

 

I did this on my AAO D150, and it works, but you have to retype the AT_OGPS=2 everytime you want to use the GPS.
Maybe someone can make a script or program for this? and also for doing the first terminal stuff.
I was thinking about this:

And maybe make a silent program, which just turns on and off GPS and shows a icon on the screen, just like the 3G and bluetooth.

 

That's a great idea. I'd be willing to donate a few £/$ to anyone who can come up with a working interface.

 

Some more information.
The outputted data is in NMEA format, so just about all software can use.
I have tested the following all with succes:
Google Earth, both pro and with Earth Bridge
Garmin Mobile PC
SirfDemo
Microsoft MapPoint 2009
Centrafuse 2

I can only get connection outside, and only to 4-5 satelites, with my BU-353 i get about 8-10 the same places.

Best Regards
Morten

 

Sierra Wireless MC8781 with the two Aspire One 3G antenna's is picking up 8 satellite. It also has to be outside but does work fine in the car.

 

I have a couple questions. Is this true Satellite GPS feature utilizing a real GPS reciever, or is this a Hardware Emulator using the Cellular Tower Signals Strength which translate into NEMA data. Does the GPS function when cellular signal is not available? Does the GPS get a Fix when the laptop is indoors? When its inside a vehicle?

 

Appears to be real satellite, not cell towers.
Works in the car.
Does not work in doors, you have to have clear view of the sky.
Works without a Sim card.
Satellite software show the eight different satellites being receivered, signal strength is higher then other external satellite receivers.

 

Does the 3G card have any type of antenna connector? Is it just a mini-pci like expansion card? Can i install one in the trap door of my AA1 A150 (empty slot) and slice a hole for the sim card as required? Is there anything additional required to upgrading?

 

viewtopic.php?f=43&t=13518&p=85018#p85018

 

Wow this looks really promising ! Will try this tonight
Anyone up for writing a small app that changes the GPS to 'on' ?

Edit:
Works like a charm

 

I agree, this is great work by the original poster in this thread

Works great!

Now, how can we make the command AT_OGPS=2 run in hyperterminal at the click of an icon on the desktop?

I no nothing about programming or writing applications!

 

Hi, does anyone know how to do this on a GTM382 card, which does not support the at_oifc command? This card is in 751h's and is the replacment for gtm380...

 

Hi everybody here, I am new of this forum,after having activated the GPS on-board of our AOA150-3G-,my opinion
is anyway that the sensitivity is poor compared with a normal SIRFIII BT 20 channels !

I was asking myself if there could be a way to improve sensitivity...

Thanksfor your reply

Giuseppe

 

The reason is that the internal patch GPS antenna in the 3G module is blinded and won't see much sky. The only way to improve sat reception with the internal GPS in the 3G module is to use an external GPS antenna. And no, the GPS antenna is not the same as the 3G or the WiFi/BT antenna.

Remember, with the location of the 3G module in the bay underneath the AAO A150, the GPS signal has to be received through the metalcover of the top casing and the metal cover of the keyboard. I'm amazed that it can get enugh signal to calculate a valid solution at all. Remember, the sats are only transmitting with 50 watts or less on the UHF band, and the distance is about 25.000 Km.
Don't expect to get a valid navigational solution if you own a french car, or any other carmake with UV filters in the windscreen and side windows, and want to use the GPS inside the car.

Since the gps part of the 3G module is using the SiRF III chipset, you should be able to use the SiRFDemo applikation to change the horizontal angle, and the cutoff dB level, which should enable you to pick up more sats, although with the result of the calculated Dilution of Precision being far higher, and the location displayed being less precise.

 

Isn't the command ATZ to write the config to the modems NVRAM so it should keep the config when rebooting the AAO. Might be AT&Z (optionally with a zero after it). AT commands are a bit rusty since I don't use analog modems any more.

 

So my MC8781 3G card is not using either of the two HSDPA antennas for satellite?

It gets great satellite reception so I assumed that it was using the HSDPA antennas, I will have to try with the antennas disconnected from the card.