Here is a farely simple way to connect your PSP to a GPS receiver:

You'll need:

- Holux GPSlim236 (~$100)
- Intec G6704 PSP Remote Control (~$11). Alternatively you can rip the connector of your original remote control.
- USB (Mini B) cable ($5-10) (don't use the included USB power cable)
- 1K 1/4watt resistor (>$1)
- Electric tape ($2 roll)

- Soldering iron
- Multimeter (for checking the connector pins, alternatively you can use just a circuit made out of a low voltage bulb and a battery)
- Razor blade (to cut and clean stuff)

Basically, you just need to cut the USB cable and PSP remote plug, figure out which wires go to the connector pins, listed below, and connect them according to the diagram:

Use caution when connecting the wires, make sure all of them are carefully insulated. You don't want to short any of them, since this may brick your PSP or GPS device.
Also, GPSlim 236 spec says that the TXD voltage may range from 3.2 to 5 V, so 1K resistor may not be enough to lower the voltage in some cases. So buy a few resistors: 5k,3k,2k,1k and see if your circuit works with a bigger value resistor first..

Once your cable is finished, test your setup with a little GPS viewer program that I wrote:
The source code is included in the zip...
Note, the program is written to work in kernel mode, so I doubt that it will work on 2+ fw..
Perhaps someone can look in to how to adjust it...

Here is the screenshoot:

So, waht's the point you ask? I am planning to plug this in to the upcoming map viewer applcation, which, of course will be able to point your gps location on a google-like map in real time... and scroll the map as you move along...

Special thanks to Art and futaris for helpping me out with serial port comm problems...

Almost forgot a disclaimer: As always, I am not responsible for any damages...

The setup, described above, should also work with some older (and therefore cheaper) holux models: GR-230, GR-231. You can get those for ~45-60 bucks.