USB GPS Mouse connection

[Anonymous]

Hi there,

let me first thank you for this great site you put up here!

And here comes my question:

I want to hook up my USB GPS Mouse (made for the notebook -
meaning it get's it's power via USB) up to my XDA.

And now I wonder if I can simply solder the data +/- cables
from the USB Mouse to the USB data +/- pins on the XDA plug
(so I could still use the same cable for ActiveSync on the PC),
or if I have to solder the data +/- cables from the USB mouse
to the serial RX/TX pins as described on the 'The XDA's connectors'
page of this site...

I was planning to hook both the GPS and the XDA up to my car
power adaptor in a kind of a Y constellation:

::::::::::::::::::::::::::::::::__________ Power
:::::::::::::::::::::::::::::::/
::::::::::::::::::::::::::::::/
::::::::::::::XDA ----------
::::::::::::::::::::::::::::::\
:::::::::::::::::::::::::::::::\___________ GPS

and use Power for both.

Maybe someone can tell me about the data hookup.

Thanks, Lars.

[climber]

I don't have answers but some things you have to consider.

1) The XDA is a slave device. I presume the GPS receiver is one too. I really wonder if they can communicate with eachother

2) Based on how you describe this you want to power the receiver from the the car. I assume you have checked the right voltage requirements for the receiver and that the powersupply can deliver the currents required for both the XDA and the receiver. My personal experience is that the latter shouldn't be too much of a problem, but it can't hurt to check.

3) Combining USB and Serial the way you describe it is not a good idea. (mark the last character '.' as in PERIOD).

Robert

[Anonymous]

Hi Robert,

thanks for your suggestions.
Indeed both (the original ActiveSync cable from the XDA and the
USB GPS) get their power off a USB port on the notebook so
this must be the same voltage requirements.

This ActiveSync cable is a combined car charging cable with an
USB 'A' type connector on the end which you can plug either into
the USB port on the notebook (where it also ActiveSync's) or into
the car's power adapter (where it only charges).
So this both same voltage. And the car power adaptor should
nominally supply enough power for both...

But I don't understand what you said about it not beeing a good
idea to hook up the USB data to the SERIAL data.

When plugged into the notebook in WinXP the USB GPS installs
a 'Prolific USB-to-Serial COM5' to emulate to the programms
working with it a com5 (or com1 or com2 depending on your
hardware settings) communications port. So I guess the data
coming from the USB GPS is just the same as if delivered via
serial cable and all the driver does is faking to be a serial port
to any programm asking for data from com5.

And I think a USB device is 'not really' a passive device as it starts
popping out ASCII data strings as soon as it get's power (no matter
if there is a device to read the data or not).

So I figure when you plug it into the XDA and tell the XDA by means
of USB wakeup (USB_VDD pin 13) that there is an active USB
connection, that it will start trying to figure out what the heck the
connected cable is trying to tell it.

And here is the tricky part where I don't know if the XDA might not
believe it is beeing Sync'ed and therefore starts ActiveSync.

Anyone with any experience or suggestions there...??

(Sorry for the rather lenghty post)

Greetings, Lars.

[climber]

Lars,

seems like you got the power all figures out

regarding the usb/serial discussion.

If I understand you correctly you can plug the USB connector of the GPS receiver into the USB port of the PC.
'somewhere' in the PC this is modified into a virutal serial port in order to enable serialport aware programs to work with the GPS receiver as well.

This is a good concept but at an electrical level that still means that the GPS receiver is connected in an USB fashion. There is nothing Serial Port about that. In a way you already pointed that out in your messages by using the word 'emulate'.

You can hook it up to the USB part of the XDA but still I doubt about the master/slave discussion of USB.

Regards Robert

[Pc-Mobile]

No cahnce.

Save yourself time/money.
Forget it.

Hi there,

let me first thank you for this great site you put up here!

And here comes my question:

I want to hook up my USB GPS Mouse (made for the notebook -
meaning it get's it's power via USB) up to my XDA.

And now I wonder if I can simply solder the data +/- cables
from the USB Mouse to the USB data +/- pins on the XDA plug
(so I could still use the same cable for ActiveSync on the PC),
or if I have to solder the data +/- cables from the USB mouse
to the serial RX/TX pins as described on the 'The XDA's connectors'
page of this site...

I was planning to hook both the GPS and the XDA up to my car
power adaptor in a kind of a Y constellation:

::::::::::::::::::::::::::::::::__________ Power
:::::::::::::::::::::::::::::::/
::::::::::::::::::::::::::::::/
::::::::::::::XDA ----------
::::::::::::::::::::::::::::::\
:::::::::::::::::::::::::::::::\___________ GPS

and use Power for both.

Maybe someone can tell me about the data hookup.

Thanks, Lars.

[Anonymous]

Hi Guys thanx for the feedback,

I spent an afternoon researching on this stuff and am very disappointed that I have to admit you are both right. :cry:

Now way (other than putting some 'intelligent' converter between the USB GPS and the RX/TX pins of the XDA) to make the USB 'language' sound like 'SERIALean'.

I think there should still be a possibility:

Let everything run via the USB, persuade the XDA it's not ActiveSync talking to it and write a driver that talks to the GPS via the open USB connection and sends the proper commands to recieve the NMEA ASCII.
And then you would still need to tell your route software to take the incoming data from the virtual (or emulated) COM port...

And when I read the above chapter once more :shock: I find this is definitly not a job for me!!

So I will just get a serial GPS an hook it up the nomal way.

Cheers and thanx again, Lars.

[KPM]

Hi,
Just read your post. I am new to pda land. Just bought a xda2
I have a laptop which I use with a gps usb mouse via usb on the laptop. Am I right in thinking that I could have bought a ps2 mouse and used a ps2 changer to usb and it would have worked??
If so can't I buy a usb to ps2 changer in order to plug into a car connection cable which has the ps2 and the xda conection and a ciger lighter plug for power? OR is there a similar cable for a usb connect for gps?
Am I missing something here?
Thanks
P