HomeHardware


Does GPS Connection Time-Out When on Computer on Standby?
SpadesFlush
Well, my experience is that, yes, it does -- sometimes.

If I go through the process of scanning for the GPS port and then proceed to get a satellite lock (which can take a few minutes) and even do a bit of navigating and then put the 'puter on standby for a little while, there is no problem resuming with an active GPS when I turn the 'puter back on to full power so long as it is a short time. On the other hand if the standby period extends to a few hours, I have to go through the whole start-up drill again.

So, my question is how long can I put my 'puter on standby without out losing my GPS active connection?
tcassidy
See if you can change the way your USB ports react when in standby. Sometimes there is an option to leave them powered in that mode. Some computers have a particular USB port that can remain powered through a standby or sleep cycle. Otherwise a cold restart of the GPS would be necessary after a relatively short time depending on the internal power capabilities of the GPS itself.

Terry
SpadesFlush
Thanks, Terry, for hopping onto my question.

Perhaps I should have mentioned that my 'puter is a Viliv S5 UMPC which comes equipped with built-in GPS. This leads to the fact that there is no USB to worry about.

Looking at the GPS port (#1) properties, I do not see any options for managing power. Where might I find what you suggest?

P. S. I neglected to mention that this time-out thing can occur even if the UMPC has not moved for instance if it is stuck to my windscreen and the car hasn't moved.

P. P. S. I have had the same experience with a USB-ed GPS with a laptop.
tcassidy
My experience with a built in GPS (ASUS R2h) left me cold to even considering that approach again. It would generally survive a couple of hours standby though and I don't think it is powered in that state.


The R2h could take 3-4 minutes to get to lock from a cold start though. What is the cold start performance of your Viliv GPS? It shouldn't be too bad. My Garmin 5000 PND (no internal battery) requires less than a minute 95% of the time.

Terry
SpadesFlush
My experience with a built in GPS (ASUS R2h) left me cold to even considering that approach again. It would generally survive a couple of hours standby though and I don't think it is powered in that state.


The R2h could take 3-4 minutes to get to lock from a cold start though. What is the cold start performance of your Viliv GPS? It shouldn't be too bad. My Garmin 5000 PND (no internal battery) requires less than a minute 95% of the time.

Terry
Yes, it takes about 3-4 minutes to get a lock from cold start, too. But I don't blame that on the Viliv because that was my experience with a laptop, also.

I have had the Viliv about a year now and I really love it. For one thing, as it is so much easier to deal with than the laptop with a USB-ed GPS was, I use it a lot more. It powers up and down quite quickly, although I am thinking about replacing the pre-installed Win XP with Win 7 to be even quicker along with other Win 7 benefits.
tcassidy
I'll stick with Bluetooth. Reconnect time is a little longer than USB (20 seconds as opposed to <6) for the R2h but the newer chipset start up times are always better even if you turn the GPS off.

Terry
xPosTech
Hi y'all

Each USB Root Hub should have the option to remain powered up. In Device Manager right click each hub and choose Properties. Under the Power Management tab you should have the option to allow Windows to turn off the device to save power. Uncheck the box.

This may or may not do what you want. The option is on the Hub, not the device itself, so you might have to try all hubs (I have four on the T91). If it works you can then turn them off one by one to find which one your GPS is on. I would turn the others off, since they would just deplete your battery for no good reason.

Also, both my laptops are running Win7. I'm not sure about Vista or XP.

Good luck

Ted

PS - Most laptops will retain power to USB if it is plugged in to power. You might test this by leaving the key in "accessory" for a while. If that is the case just find an unswitched point on your fusebox to connect to.
tcassidy
If the Viliv v5 is like my ASUS R2h UMPC, the internal GPS does not appear on a USB port. I know, I looked at all the hubs. It is probably a true serial device, maybe why Mobile PC can't find it! There seems to be no way you can see or change when it is powered.


Terry
SpadesFlush
Thanks for thinking about this Ted but perhaps you missed my post above where I mention that my GPS is built into the UMPC, not connected via USB. I know there is the power option for USB ports but that does not exist for COM ports. As it is, the GPS shows on the COM1 port.
xPosTech
Good point, Terry. Usually the only way to add a device to small laptops/UMPCs is PCIe or USB even though you sometimes can't find the device logically. If it is USB it has to use one of the hubs, though. It is actually easy to add an internal device to USB if you can find the physical room somewhere.

Hopefully the hub hosting his GPS can remain powered up one way or the other.

Ted
xPosTech
Another good point. I'll admit I know nothing about Viliv. If it shows in Device Manager as a Com1 device you're probably stuck.

It's understandable, though. They are transferring a lot of software overhead to hardware. And the serial device on a chip is getting pretty sophisticated these days. And they don't have to convert it to serial S/W wise.

And I am NOT beatin on this dead horse anymore.

Ted
tcassidy
Too bad, I was about to rip apart my R2h and see how that GPS chip is physically connected!! Maybe I could splice in a battery.

Terry
xPosTech
I've been modifying (not added any peripherals since the mid nineties) computers since the late sixties. Now that I'm retired I didn't think I would do it anymore but these (relatively) inexpensive laptops make it fun again.


Ted
SpadesFlush
... If it shows in Device Manager as a Com1 device you're probably stuck.

...
I am not sure what you mean by "stuck," Ted, but I infer you mean I have to live with whatever the UMPC is doing with regard to powering the GPS. I have pawed through Device Manager and I cannot find anything that might be remotely applicable to managing the power to the GPS function.

So, I guess I am stuck.
laptopgpsworld.com About