Closer To The Final Replacement Of Stick


Radek

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Joined
Oct 13, 2005
Messages
871
Hi,

I made significant progress with my project of total replacement of GP2x's stick. I have now a prefinal version of my logic converter and successfully connected it to GP2x and controlled it from external pad.

First the circuit board:
close18kl.jpg


It's using socket adaptors for chips because I would like to be able test different ones. Final (production) version will have chips soldered directly and will be shrinked by few mm.
(don't worry - it will fit inside GP2x without any problems)

Now the pad - it's Saitek P2500 hacked quickly to act like a input device for my logic converter:
close23tg.jpg


Time to make some wiring into GP2x itself. There wasn't any soldering here just smart trick to connect to existing pins at the back of GP2x's mainboard:
close34st.jpg


Does it really work? Yeah and everything is powered directly from built in AA batteries in the GP2x (Saitek pad is used only for its switches - it doesn't consume any extra power):
testing10pn.jpg


Dreaded diagonals works of course too but behave very nicely now :)
testing26kd.jpg


But to the point - the games. Prince Of Persia running in Outcast first. Basically unplayable using stock's stick. How it handles now? As it should - all problems with accidental jumping, hitting undesired directions and other crap are gone!
game20te.jpg


Turricans... I'm very big fan of these and Atari ST versions are pretty good. Not that terribly bad with original stick but... running and jumping now is... delicious?!
game48dk.jpg


Another trouble maker - the Nebulus - very hard to play with you know what. Fixed!
game64pg.jpg


Gods is another my favorite of all times. Really great on the Atari ST. Awesome graphics and animation. Played it for few minutes using the P2500 pad. I don't have to tell how it was, have I?
game71ga.jpg


Now the bad things...

No bad things except that I still doesn't have a pad or stick what would fit inside GP2x and would be good replacement for the stock one. Any ideas are very welcome.

Of course my logic converter works only for stick - it's not universal interface for all GP2x's buttons. That wasn't goal of my project and adding such functionality is trivial because there will not be need of any signal translation (just connecting more wires).

The good things are:

- my logic convert works and works well
- it will fit inside GP2x
- it is powered directly from batteries and it can run even at 1.5V
- it is compatible with any 4-switch based pad or joystick
- it can be used simultaneously with stock stick (for connecting external pad like in my experiment)
- it doesn't require soldering to be connected to GP2x's mainboard (because the stock stick's pins are long enough to use different method)
- prefered method of removing original stick is to just cut it off from mainboard
- fitting a replacement might not require soldering except for wires to the logic converter. But how exactly it should be done is unknow until replacement will be found

That's all for now.

What are you thinking?

If you want to experiment yourselfes I'm willing to make some units for you.
 
I'm gonna hold out until this is more complete but I'm looking forward to the end result! Also, have you looked at the NGage and Game Gear Dpads as suggested? If so, are they unsuitable for some reason?
 
Glad to see that you have got something working now, as I know you have been putting lots of work into this as well as other projects.
 
Good, finally a proper Dpad.

All I can say is ewww Saitek, bleh... (it was cheap right?)

Also I was thinking...

DaveC has these custom joystick cap things...

we are building our own custom replacment board/adaptor/module:

Why not make the 'top' part of the dpad fit thru the small hole for the old joystick,
and use a carbon membrane pad with a mass produced pcb.

It has a matching bottom part, that it could be screwed/glued onto.
the bottom part makes contact with the carbon pads and control PCB.

http://www.olimex.com/pcb/index.html for the PCB. (they are supposedly the cheapest)

for the membrane pads... there are LOTS of manufacturers. (LOTS... looking may take awhile)
 
I'm just hoping we get to the point where I plug in a USB gamepad and don't need to rip open the GP2X the fix the problem.
 
Radek posted on Mar 11 2006 at 07:27 PM said:
Hi,

I made significant progress with my project of total replacement of GP2x's stick. I have now a prefinal version of my logic converter and successfully connected it to GP2x and controlled it from external pad.


Cool, now you should do a test of battery life. Use the same exact batteries charged for the exact same time and let a video loop or something. Test without powering the chips and test with the chips. I would be interested to know the actual difference in battery life. The difference SHOULD be not much but you never know.
 
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First thanks for good words!

And who made me Guru so suddenly!? :)

Now it's time to answer some question...

BenScar posted on Mar 11 2006 at 09:41 PM said:
Now that looks like fun! How easy was to solder straight to the GP2x board?

It wasn't because there wan't any soldering done on GP2x's mainboard.
It isn't necessary.

IntenseWage posted on Mar 12 2006 at 12:34 AM said:
Like I suggested in the old thread, take a look at N-Gage pads.

I was looking at them but...
There are some issues what I have and don't know how to solve them.
First is the front panel of GP2x - what to do with it? Drill or cutoff? I will
ruin my GP2x trying as I don't have skills for working with plastics.
You know - I would like to use my GP2x as usual and I can not go too
invasive. Therefore I'm asking others for solution of that problem. I will
happily made custom PCB for any idea.

Personally I would prefer an another stick but with 4 proper microswitches.
This would be most elegant solution imho. Not that good as a dpad but still
far better than stock stick.

Series-8 posted on Mar 12 2006 at 04:36 AM said:
Good, finally a proper Dpad.

All I can say is ewww Saitek, bleh... (it was cheap right?)

Yes of course but it's quite decent and comfortable for my hands.

Series-8 posted on Mar 12 2006 at 04:36 AM said:
Also I was thinking...

DaveC has these custom joystick cap things...

we are building our own custom replacment board/adaptor/module:

Why not make the 'top' part of the dpad fit thru the small hole for the old joystick,
and use a carbon membrane pad with a mass produced pcb.

A good idea!!

However I there is problem with needed parts. I can only buy what I can find in available shop - making custom plastic parts is out of question for me.

Series-8 posted on Mar 12 2006 at 04:36 AM said:
It has a matching bottom part, that it could be screwed/glued onto.
the bottom part makes contact with the carbon pads and control PCB.

http://www.olimex.com/pcb/index.html for the PCB. (they are supposedly the cheapest)

for the membrane pads... there are LOTS of manufacturers. (LOTS... looking may take awhile)

Thanks for the link. Having more choices for manufacturing is always good thing.

DijiTao posted on Mar 12 2006 at 07:38 AM said:
I'm just hoping we get to the point where I plug in a USB gamepad and don't need to rip open the GP2X the fix the problem.

I'm hoping for that too but unfortunately it will need software support (perhaps could be done via driver in the firmware?) and probably USB powered breakout box. It'd be real great for playing games when connected to a TV for sure.

I was using external pad because I didn't have any other controller but I wanted to make the final test of my circuit.

The ability to connect external controler will be just additional possibilty.

For soldering (and such things) I wasn't soldering anything inside GP2x to connect wires. There are other, easier methods.

DaveC posted on Mar 12 2006 at 07:45 AM said:
Radek posted on Mar 11 2006 at 07:27 PM said:
Hi,

I made significant progress with my project of total replacement of GP2x's stick. I have now a prefinal version of my logic converter and successfully connected it to GP2x and controlled it from external pad.


Cool, now you should do a test of battery life. Use the same exact batteries charged for the exact same time and let a video loop or something. Test without powering the chips and test with the chips. I would be interested to know the actual difference in battery life. The difference SHOULD be not much but you never know.

Why I was expecting that question from you? :rolleyes:

Let me say that power consumption is counted in µW per chip. But I just turned my GP2x on running Noiz2a with circuit being powered up.
(actually there are more factors in cmos based chips to consider like a freqency of operation - it can increase power drain significantly after 500-1000KHz... but I doubt that you can move your fingers that fast ;) )
 
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Radek posted on Mar 12 2006 at 10:53 AM said:
(actually there are more factors in cmos based chips to consider like a freqency of operation - it can increase power drain significantly after 500-1000KHz... but I doubt that you can move your fingers that fast ;) )
Damn my overactive imagination :p

It looks great, although I would have thought using the Dpad in one hand and the controls in the other would be rather uncomfortable.
 
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Aninhumer posted on Mar 12 2006 at 12:10 PM said:
Radek posted on Mar 12 2006 at 10:53 AM said:
(actually there are more factors in cmos based chips to consider like a freqency of operation - it can increase power drain significantly after 500-1000KHz... but I doubt that you can move your fingers that fast ;) )
Damn my overactive imagination :p

It looks great, although I would have thought using the Dpad in one hand and the controls in the other would be rather uncomfortable.

That was for testing only if it works in actual aplications and games. Don't assume that it will be so! I just hadn't any other controler to use for that purpose. But I must say that even in such awkward position I could finish level in the Prince Of Persia - a feat what was impossible for me using stock stick.

The taste of improved control was great... but still there is some work to do with mechanical replacement of GP2x's stick. At least it is starting to be real possibility.
 
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sounds great..
hope we find a good replacement pad/stick soon..
cant wait to mod my gp2x ;)
 
To answer DaveC's question about power drain of the converter circuit:

My GP2x worked over 3.5 hours using fully charged GP2100 batteries running noiz2sa game with it.

I will try later to run it without it but I doubt that difference is measurable.
 
hmm what about the dpad of the original cube controller its quite small...
i have a broken one lying arround here (the anologstick is broken)
 
Looking good, damn good.

I got a couple of the PCB joystick units earlier in the week, but this weekend has been kind of a write-off, so hopefully I'll have time next week to try mods on those to try and improve the feel.

One of my intentions is try a restriction mod to turn it into a 4-switch unit, and make use of your circuit, Radek, so that the external appearance is unmodified.

My other thought was to use a hole cutter or stepper bit to cut out the original collar, and replace it with some kind of custom clip-in or screw-in job.

However, that's my problem: Too much thinking and not enough doing!

I'm hoping to have my own GP2X units within the next week or so, and then I can take them apart and do some of my own hacking, as well as see how much space there is inside the casing. Perhaps it might even be easy enough to cast new ones, if there's not too many fiddly internal supports.

The only drawback to people like myself buying these additional sticks is now perhaps the designers in ALPS are sitting back thinking, "Hey, we must be geniuses. Those joysticks are selling like hot cakes - We must have done something right!".

:(

Looking forward to seeing more of your work...
 
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