CPU clock speed

[exp3000]

another quick question. Why do people recommend 111mhz? what is the benefit of having lower clock speeds and what do you use to lower the clock because map this only allows for 333mhz-222mhz.
tnx in advance.

[UltraDude]

It finds and locks faster in 222/111 mhz.. in fact it doesn't even work for me in 222/333 mhz.. only works in 111 mhz for me. You can put it on 111 mhz by pressing Start -> GPS Info -> Press Down until it shows 111 mhz for CPU.

[Liquid Smoke]

yeah i only see the option for 333mhz and 222mhz, how do i get to 111mhz?

and i just use 222mhz cuz it uses much less battery so it'll last longer, unless u got a car adapter it wouldnt matter i guess, but 222 seems to work at the same speed as 333 for me, so i just stay lower to have the processor working less.

[cydus21]

the option its not at the start menu. u have to go to "GPS info" and press down till u see 111mhz at the bottom left hand corner of the top main row of information.

by the way i always get lock no matter which clock i use.. and fast too.. i'm using GPSlim 240 thou

[deniska]

The psp seem to produce some EM frequencies which may interfer with gps receivers...
This interference does not affect GPSlim receivers that much because they usually are not that close to PSP as PSP-290 unit (You can actually see some sensitivity loss if you bring the unit too close)

lowering the cpu/board clock seem to lower the EM interference too... but it's mostly visible to PSP-290 users

[UltraDude]

The psp seem to produce some EM frequencies which may interfer with gps receivers...
This interference does not affect GPSlim receivers that much because they usually are not that close to PSP as PSP-290 unit (You can actually see some sensitivity loss if you bring the unit too close)

lowering the cpu/board clock seem to lower the EM interference too... but it's mostly visible to PSP-290 users

Hmm..so if one were to create an extension cable for the mini usb and have the PSP-290 at a distance from the PSP itself.. would that give us 290 users better performance? (and at higher clock speeds)

[Nylon32]

I may give the extension cable idea a try, I'll report back on how it went

:Edit
Well after dome very difficult soldering I managed to adapt a mini usb plug from an old mp3 player, and attach that to the end of an existing cable which allowed me to extend the usb part then all I had to do is secure a couple of wires to the DC jacks either side, and I'm pleased to say that it worked in less than a minute getting a fix on 4-5 satellites, as you can see from the picture this sort of set-up isn't ideal but the the improvement in signal strength (from 2-3 bars to 4-5 indoors) and accuracy is amazing.

http://img136.imageshack.us/img136/9829/dsc00367vx3.jpg

[exp3000]

I may give the extension cable idea a try, I'll report back on how it went

:Edit
Well after dome very difficult soldering I managed to adapt a mini usb plug from an old mp3 player, and attach that to the end of an existing cable which allowed me to extend the usb part then all I had to do is secure a couple of wires to the DC jacks either side, and I'm pleased to say that it worked in less than a minute getting a fix on 4-5 satellites, as you can see from the picture this sort of set-up isn't ideal but the the improvement in signal strength (from 2-3 bars to 4-5 indoors) and accuracy is amazing.

http://img136.imageshack.us/img136/9829/dsc00367vx3.jpg

Dude, thats amazing, im gonna try this over the weekend.

[deniska]

can someone look for an affordable extension cable (usb mini-b to mini-b)
I found one, but 30 bucks sounds a bit too hight for a piece of wire... :-(
http://industrialcomponent.com/usbstuff/cellext.html

[UltraDude]

can someone look for an affordable extension cable (usb mini-b to mini-b)
I found one, but 30 bucks sounds a bit too hight for a piece of wire... :-(
http://industrialcomponent.com/usbstuff/cellext.html

Had no luck finding anything cheaper :(

Would this cable work though? Im not sure what those 2 pins on the sides are for..are they just there ..or do they ground the unit?

[r2000]

Had no luck finding anything cheaper :(

Would this cable work though? Im not sure what those 2 pins on the sides are for..are they just there ..or do they ground the unit?

I have the same doubt.

But here is one extension cable which is considerably cheaper:
http://pc-mobile.net/guge.htm

[r2000]

The extension cable:
http://pc-mobile.net/cmue.jpg

[An0nJ0hn]

I have the same doubt.

But here is one extension cable which is considerably cheaper:
http://pc-mobile.net/guge.htm

Nice find, did you order one?

[deniska]

I contacted the manufacturer, and they going to mail me a couple of those cables - I'll let you know if it works out...

[An0nJ0hn]

I contacted the manufacturer, and they going to mail me a couple of those cables - I'll let you know if it works out...

Did they say how long it would take for them to arrive and/or which shipping company they use?
I ordered a couple of them, hopefully they work out.

Deniska (or anyone else that knows) : So you think that the two metal pins on each side of the PSP-290's USB plug are for electrical current and/or ground? Does anyone have a meter that they could somehow wire in there and check? Do you think that might do harm to the PSP itself or the receiver? I'm just wondering, I don't really have much experience with this stuff.

[Nylon32]

Did they say how long it would take for them to arrive and/or which shipping company they use?
I ordered a couple of them, hopefully they work out.

Deniska (or anyone else that knows) : So you think that the two metal pins on each side of the PSP-290's USB plug are for electrical current and/or ground? Does anyone have a meter that they could somehow wire in there and check? Do you think that might do harm to the PSP itself or the receiver? I'm just wondering, I don't really have much experience with this stuff.

I've Messed around a little bit with the cable I made and so far I've found that the DC output jacks at the top are +5v on the left and Ground on the right, (The ground doesn't need to be connected for the GPS to work as the usb has a ground connection), a word of warning though be careful not to cause any short circuits as the psp will make a clicking noise and cut off it's power, so far I've accidentally done it a few times but theres a risk of blowing a diode or something else


::edit
Well I decided to test it the pins were actually giving 5v out and it turns out they don't, the V+ pin runs at 3.5-3.57 volts which is that the PSPs battery runs at (rated 3.6v) the 5v DC out figure seems to be quoted on a lot of sites.

Here's the pic as proof
http://img501.imageshack.us/img501/636/dsc00384td6.jpg

[An0nJ0hn]

I've Messed around a little bit with the cable I made and so far I've found that the DC output jacks at the top are +5v on the left and Ground on the right, (The ground doesn't need to be connected for the GPS to work as the usb has a ground connection), a word of warning though be careful not to cause any short circuits as the psp will make a clicking noise and cut off it's power, so far I've accidentally done it a few times but theres a risk of blowing a diode or something else


::edit
Well I decided to test it the pins were actually giving 5v out and it turns out they don't, the V+ pin runs at 3.5-3.57 volts which is that the PSPs battery runs at (rated 3.6v) the 5v DC out figure seems to be quoted on a lot of sites.

Here's the pic as proof
http://img501.imageshack.us/img501/636/dsc00384td6.jpg

So when I get my cable I need to add two additional lines; a positive (left) and a ground (right) (I know you said It isn't needed but I'd rather be safe than on to my back-up PSP). Will it matter what gauge wire I use? What caused/es the short circuit to occur? What should I avoid? I may try to make a cable before the two i ordered arrive if I can find the USB mini-B 5 pin receptacle.

[Nylon32]

The type of wire doesn't really matter just make sure that it it isn't exposed in anyway, I find it resets itself if I:


Accidentally connect V+ straight to Ground
Press the wire in too firmly in to the jacks on the top of the PSP
or if any exposed wire touches the metal part of the USB cable


So long as your careful don't have any loose, exposed wires, it will work fine.

[An0nJ0hn]

The type of wire doesn't really matter just make sure that it it isn't exposed in anyway, I find it resets itself if I:


Accidentally connect V+ straight to Ground
Press the wire in too firmly in to the jacks on the top of the PSP
or if any exposed wire touches the metal part of the USB cable


So long as your careful don't have any loose, exposed wires, it will work fine.

By "type of wire" does that include thickness and composition? BTW thanks for your help and patience.

[Nylon32]

Well this is the wire I'm using:
http://www.maplin.co.uk/module.aspx?ITAG=SPEC&ModuleNo=9910&doy=15m5#spec

It's a 0.08mm Multi core copper wire, but I don't think that its composition or thickness are that important, but then I'm not really familiar with wire gauges

I hope this helps sorry I can't give a more comprehensive answer.

[deniska]

Nylon32, thanks for your report...
I am still waiting for my mini-USB extention cables to arrive... If the cable proves to be effective in improving psp-290's reception, I may try to talk the manufacturer in to producing a special PSP version so no extra wires a nesessary...

If you have time and courage, it would be interesting to find out if raising the incoming voltage (to power the psp-290 unit) to 4-5 volts would increase the sencitivity even further...

Some people reported that psp-290 exibits worse sensitivity then PSP's battery is low... so perhaps raising the voltage (by powering it from outside sourse (3 aaa batteries) may do the oposite....

Of course, there is a chance of bricking the gps, unit, so I'll understand if you don't want to mess with it...

[Nylon32]

I might be able to get a hold of a fairly accurate variable DC output power-pack, so i'll give this a try.

::edit well the DC power pack didn't work at all. I checked all the connections for any short circuits or loose connections and still the unit refused to activate. but I'll try and find a few AAA batteries and see it they give me anything.

[deniska]

What was your exact connection diagram?

What you probably want to do is to conect the (-) of the battery to the USB ground wire (4) (see these diagrams: http://pinouts.ru/Slots/USB_pinout.shtml)
It should go to both PSP and GPS device.

Then the (+) of the battery goes to (+) port of GPS only! (this should be one of those side wires)

[Nylon32]

Well I wired up the power pack similarly to the way you suggested, but it had a ground terminal so I used that and connected the GPS and PSP to that terminal and the variable V+ terminal to just the GPS and it didn't give me any results.

After that I tried wiring it exactly as you said, but I could only get my hands on 4 fully charged, but quite old 1.2v Rated Rechargeable batteries, these too didn't work but this could have been due to them not having enough voltage left in them. If I can find some new 1.5v AAA's then I'll give it another try

Also I tried just connecting the GPS using my extension cable and just using the PSP output and again I was consistently getting a lock on 6 satellites and at one point while driving was getting a lock on 8 satellites, and I never noticed it drop the connection, By how much do you think a higher voltage could improve the signal by?

[deniska]

it's hard to say...

[Nylon32]

I managed to get the GPS to work using a separate power supply, I used 2 AAA batteries that were giving 1.8v each the pic shows it all wired up but the wire came loose from the top of the PSP as I took the picture.

it also does seem to activate quicker, taking less than a minute to get a lock on 4 satellites

Link to the picture:
http://img382.imageshack.us/img382/404/dsc00387hp3.jpg

I'll give it a try with 3 AAA batteries and see if it gives better results

btw I'm doing all this at 111mhz as it still seems to be best for getting a lock on satellites quickly

Edit::

I've just tried it with 3 1.5v AAA batteries (In total giving 5.3-5.4v as they're new batteries) and it got 2 satellites in view instantly a few more within a few seconds and a lock soon after that. Seeing as there don't seem to be any immediate adverse affects I'll try seeing how it behaves while on the move

[deniska]

cool, let me know if you find anything else..
thanks for your research....

[An0nJ0hn]

I may give the extension cable idea a try, I'll report back on how it went

:Edit
Well after dome very difficult soldering I managed to adapt a mini usb plug from an old mp3 player, and attach that to the end of an existing cable which allowed me to extend the usb part then all I had to do is secure a couple of wires to the DC jacks either side, and I'm pleased to say that it worked in less than a minute getting a fix on 4-5 satellites, as you can see from the picture this sort of set-up isn't ideal but the the improvement in signal strength (from 2-3 bars to 4-5 indoors) and accuracy is amazing.

http://img136.imageshack.us/img136/9829/dsc00367vx3.jpg



I got my cable today and I second Nylon32's results. I filed down the sides of the cable so that the power rods would fit into the sides of the mini usb female plug's casing. Then I took some spare cable I had and used it to connect the positive power. Nylon32 is correct about it working fine without the ground line although I will likely add it when I figure out how I'm going to make my cable permanent. I used no soldering and basically did a poor job of it but it works which is what I wanted to find out. I managed to get three bars reception indoors and under some pretty heavy rain today using the cable. It would be pretty sweet if we could get some proper cables made although I'm not giving up on making my own.

http://img475.imageshack.us/img475/8246/dsc00072sn6.th.jpg (http://img475.imageshack.us/my.php?image=dsc00072sn6.jpg)

http://img475.imageshack.us/img475/5707/dsc00071vh4.th.jpg (http://img475.imageshack.us/my.php?image=dsc00071vh4.jpg)

http://img475.imageshack.us/img475/3218/dsc00070bx4.th.jpg (http://img475.imageshack.us/my.php?image=dsc00070bx4.jpg)

[Nylon32]

heh, I got my cable a couple of days ago and I modified it in exactly the same way

[An0nJ0hn]

heh, I got my cable a couple of days ago and I modified it in exactly the same way

Nice! That's pretty funny. What are you gonna use for connectors to the PSP and GPS receiver? I'll have to hit the local stores and see what they have as far as parts that I could cap the cable with. Let me know if you have any ideas.

[mrplov]

Isnt it possible for an application to raise the power-output to a usb-device?

[MemorX]

Isnt it possible for an application to raise the power-output to a usb-device?

I think that would be difficult. The battery of the PSP is 3.6 V, and without some kind of hardware to increase the voltage, and thereby decreasing the current.

Btw: This discussion is exiting, I hope this kind of cable will be available for sale soon :)

[An0nJ0hn]

Isnt it possible for an application to raise the power-output to a usb-device?

Unfortunately, the PSP-290's power is not supplied via the usb port.

Alright, I figured out what I'm going to use for the GPS end of the cable and it works quite well:) . I got the power line adapted but still haven't added the ground line yet, although this technique will work the same for the ground line. I'll post a picture of it I tomorrow.
The PSP end of the cable is another story. It is going to be difficult for me to duplicate the flexing rods of the PSP-290. I looked everywhere but one store (only open during the work week) and had no luck:( . Any suggestions are welcome.

[Nylon32]

I'm experiencing essentially the same problem this is what I've done for the GPS end of the cable:
http://img295.imageshack.us/img295/3673/untitledod8.th.jpg (http://img295.imageshack.us/my.php?image=untitledod8.jpg)
http://img528.imageshack.us/img528/9559/untitledzg0.th.jpg (http://img528.imageshack.us/my.php?image=untitledzg0.jpg)
which seems to work very well, but the PSP end is proving to be a bit of a problem, it would probably have to be something using a spring , but making a mechanism that small is going to be difficult

[yipchunyu]

i still can't make it as 110 hz. anyone can capture the picture to illustrate? Press down (once) to make it 110 hz within GPS info?

sorry, it works now. the version i use can't make it work. I dl a newer version and it works now.

[An0nJ0hn]

Here are the pics of my progress thus far. As you can see, I added the ground line. You can see that I went in a little different direction than Nylon32 did with his cable. I am attempting to duplicate the connector plates that are in the PSP. Because the PSP-290's poles retract, this works very well and I have yet to lose connection on this end of the cable no matter how much I move it around.

Parts:
So far I've used the mini USB 5-pin extension cable, some wire I found in my tool box (24 AWG) and two .187" male quick disconnects that I filed down and bent to fit into the sides of the mini usb female receptacle. I also used a fair amount of electrical tape.

Tools:
I don't have any electrical tools so I have been using my Leatherman. I used the knife to prep the wire, the file to file the female usb and the quick disconnects down and the pliers to bend the male quick disconnects.

I'm still thinking about the PSP side of the cable as it is the last remaining issue. Anyhow, here are the pics, I hope you enjoy.

http://img508.imageshack.us/img508/274/dsc00080zv9.th.jpg (http://img508.imageshack.us/my.php?image=dsc00080zv9.jpg)
http://img508.imageshack.us/img508/6203/dsc00078fv3.th.jpg (http://img508.imageshack.us/my.php?image=dsc00078fv3.jpg)
http://img508.imageshack.us/img508/6721/dsc00077mg5.th.jpg (http://img508.imageshack.us/my.php?image=dsc00077mg5.jpg)

[Nylon32]

I may have found a semi-permanent way of getting the PSP end of the cable to stay connected; I’ve just started experimenting with it but does seem to work quite well.

http://img525.imageshack.us/img525/1203/upld3po5.th.jpg (http://img525.imageshack.us/my.php?image=upld3po5.jpg)

http://img525.imageshack.us/img525/6204/upld1ck5.th.jpg (http://img525.imageshack.us/my.php?image=upld1ck5.jpg)

http://img181.imageshack.us/img181/1505/upld2tv3.th.jpg (http://img181.imageshack.us/my.php?image=upld2tv3.jpg)

I’ve filed the edges down so the spring fits in better much like An0nJ0hn did with his cable, fortunately this cable seems suited for all the modifications I’m making to it.

Once I get the other side done I’ll do some tests and see how well it works.

Edit: I'll also put up some more details on how it was made for anyone who's intrested.

[An0nJ0hn]

Great job man.

Is that from the laptop you told me about or did you find it somewhere else?

I'll try to post pics of my progress when I get back from work this evening. Splitting those two pins proved to be a real task but I did manage to get it done and one of them mounted and attached to the power line.

[Nylon32]

Great job man.

Is that from the laptop you told me about or did you find it somewhere else?

I'll try to post pics of my progress when I get back from work this evening. Splitting those two pins proved to be a real task but I did manage to get it done and one of them mounted and attached to the power line.

These springs were actually taken from a broken floppy disc drive, I've nearly finish the cable, just need to find a good way of keeping the springs in position.

[An0nJ0hn]

Well apparently work is in a rain delay so here are the pics of the power pin that I attached to the PSP end of the cable. I'll have to get the second pin (ground) attached sometime today (if I end up not working) or tomorrow.

http://img164.imageshack.us/img164/2148/dsc00082ei9.th.jpg (http://img164.imageshack.us/my.php?image=dsc00082ei9.jpg)
http://img502.imageshack.us/img502/3451/dsc00081zz5.th.jpg (http://img502.imageshack.us/my.php?image=dsc00081zz5.jpg)

It seems to work great so far. No matter how much I try to disconnect it by moving the cable around the power to the GPS receiver remains on. I merely glued the pin casing to the usb plug but it's holding very well.

As you can see if you look at the full resolution picture, I had to do a bit of filing to the USB's casing as well as the pin's casing in order to get the pin to properly line up with and into the connection plate in the top of the PSP. I agree with Nylon that this extension cable has proven to be very much up to the task of being modified. It is a very solid cable.

[Gene]

Isn't it possible to create a plug that covers the 2 screw holes, and use that as ground? just like the actual 290. Or are the screw holes not ground?

I just think it would be easier to develop a cord that would just screw to the top rather than try and make a spring loaded peice of metal.

[Nylon32]

unfortunately the screw is very unlikely to be connected to ground especially as the +V pin is right next to it, also the only real problem with not using something spring loaded is that you get a very loose connection as I found out when I first stared testing my cable, also if you use a material that doesn't bend or spring back then you could risk damaging your PSP's DC out connectors.

[gil7]

I press the down button after going into GPS info mode. And it doesn't change the Mhz speed to 111. I have it currently on 89 Mhz. Which is set up at that since I got this software onto the PSP.