AGPS Upload available (for testing)

AGPS upload can now be tried by the greater public starting from versions BT747_2.X.1387 (Desktop) and BT_J2ME_0_2_97.

You'll need to have the AGPS data (a file with .EPO extension) available on your system OR get a hold of the URL to fetch the data from (login + password + site & path). Despite two requests for authorisation sent to transystem, I did not get a reply back. Getting a hold of this information is 'as simple' as looking in the log of a decent firewall, or googling around with the right keywords.

Some users said the upload is slower than with the other tools, but they also demonstrated that BT747 is more secure. The other tools do not seem to respect the acknowledge data sent by the device, whereas BT747 does. Waiting for the acknowledge makes the upload slower.

It has also been reported that the AGPS upload works over bluetooth. The device manual says this should not be done. I guess that it fails if the handshake mechanism is not respected, but BT747 respects it (as said earlier).

The functionality has been around in the development streams for a few months now. The important step of propagating the error messages to the user has been done. You can expect two types of errors:

  1. there is a problem with the data download (getting it from the web or from the file),
  2. there is a problem with the data upload (sending it to the device)

In the latter case, it is best to proceed to a clear of the AGPS data and then try again if you want.

The devices that have been tried up to now did not support more than 7 days of data. Uploading more than that does not seem to be harmfull, but is discouraged anyway.

The GUI of the PDA version currently does not have AGPS upload available. If there is enough interest this can be done - the main reason for this limitation is that the code to get the data from the network is different for each platform. The J2SE environment has integrate FTP download capability, whereas J2ME and SuperWaba do not. A simple FTP Client had to be implemented for J2ME and has to be ported to SuperWaba.

Some users have already validated this on their device and Dirk Haase has been quite involved in testing it during development.

The upload functionality will evolve further to make operations smarter (upload usefull data only, download/upload only if data is out of date, ...).


Bild von Imroy

What advantage does AGPS give?

Ok, so I have this 53KiB file and can download it to my GPS receiver (i-Blue 747 A+). What does this give me? Is it simply to avoid the 30 second TTFF when it's been off for more than a few hours? Or something else?

Bild von mdeweerd

AGPS utility

I think it mainly serves that purpose, yes. I also think that it enables you to get a fix in difficult conditions (when the device has been off for a long period).