Bacteria - Ipaq 3600 PDA resurrected, improved! *DONE*

[bacteria]

The description in the forum title for "Handheld Hacking" states " (This forum is for pre-built handhelds, NOT custom made portables!)". Modding an old PDA I figured would be ok here in this section as it is a "pre-built handheld" - as a PDA it is a pre-built handheld. This Handheld Hacking section is wide-angle after all!


Ok, I bought a rather nice Compaq Ipaq 3660 about 7 years ago for (ouch) £550. I used to be in professional sales so figured one of these would be useful - it was, but I really didn't need it - it was a gadget (boys and toys!), wished I bought a cheap one at the time, not a colour one - would have been about half the price, or less, oh well....

The battery (Li-ion) was 5v (no idea of its mAh) but only lasted for 1.5 hours, perhaps because the battery was so thin (about 3mm thick)? After years of not using it (probably about 5 years), I thought I would boot it up and if it worked fine, e-bay it; however the battery is completely dead and won't recharge, so I therefore can't sell it (but I can mod it!). I then looked on e-bay and google for replacements, no luck, the model is long gone; so I thought "ok, its junk, nothing to lose, it's only fit for the bin anyway"; plugged it into the gadget designed to hold it while it runs via mains, and USB to computer (the docking station) - works fine; just the battery was dead.

I then thought - the buttons on the PDA were always fiddly to press, the D-pad was not easy to use and when you were using it your finger was right over the speaker (so muffled sound).

How about, I thought, modding it to take new powerful batteries, new case and new buttons and speaker?

Here is the new project (I will rivert to finish off the briefcase for my Nintendo 64 Advance project when I want a break from this project, I can easily do two projects a the same time).

The PDA had those horrible screws, I had to use my dremel to slice a groove in the screws to undo them (hoping not to cause any damage). After an hour or two I managed to get the touchscreen and mobo out of the case. I then had similar problems with the screws from the docking station, made some shavings off the plastic case with the dremel, saw all was safe, so hacked away at the case to slice grooves in those screws and remove the small mobo from within.

Hooked it all up, as you see, it works. The D-pad and buttons are on a small mobo which has a tiny male connector with lots of connections on it, presses into its female connector on the main mobo, supplies the power, etc to it. I will have to hot glue them together when I am ready to.

Fortunately, I saved Ipaq 3660 games, applications and emulators at the time onto disk, so I have them. It would be nice to have the facility of a good PDA again, updated, improved and more powerful!! (hence the benefits of such a mod).


Objectives:

(1) use a large battery pack - I can use a TI card to reduce the voltage to 5v. It would be nice to aim for several hours power at a time instead of only 1.5 hours.

(2) replace the D-pad with a better one (NES one).

(3) replace the buttons with tact switches (they are currently tiny metal press domed metal bits).

(4) custom make a case.

(5) better speaker.

(6) external connector for the USB port.


Worth a try - nothing to lose! The PDA is fine, only 200Mhz, but built-in MS Office pocket 2000 and other applications, including MP3, etc; and 64Mb ROM.

Progress so far - all works:



I can't find the voltage positive and negative terminals as the connectors are too tiny, however I can wire a battery directly to the terminals on the power-in from the external power supply (5v), which will do the same job.

I only have one chance at this project to make it work, I have no spare parts, no pinouts (I need to find everything myself), if it fries, it goes in the bin as the project will be dead. I might therefore be able to finish this project if I carry on being careful, or it might finish abruptly - let's see!!

Questions - can you help please?:

(a) I know it is somewhere on the forum - how do I make it so the system runs off batteries all the time, when I plug in the mains, it diverts power from the batteries straight to the mains to feed the system? Alternatively, if I just plug in the mains (5v) into the system and it is already running on batteries (5v), would that cause any damage to the system, as in effect this is parallel?? (if this is ok, problem solved) - anyone know??

(b) Using the TI card, the PTH08000, it can regulate voltage from around 3v-5v by external resistor. What resister would I need therefore to get 5v from a battery pack running at about 7.2v or 7.5v please?

[bacteria]

I have identified where a number of connections from the front (top pic) of the small board go to the pins on the reverse of the board (the white male plug in bottom pic), however we are talking micro electronics here. I can identify the connections but can't solder that small (under .5mm between the wires). This would allow me to save a small amount of breadth, not much though; I will have to solder my joints directly to the small mobo in the usual ways.

[vskid]

I have almost exactly the same PDA, except its a 3600. Its in about the same condition, too, dead battery and all that fun stuff associated with old stuff. I want to replace the battery, but I was thinking of replacing the pack itself with rechargeable AAs. The stock battery is 3.7v (all Li-ions are), so 3 batteries will hopefully work. Only problem is figuring out where to solder the new batteries, I'll probably end up taking the old battery apart.
I'm also trying to LED mod the screen, but the way the backlight works is making that slightly difficult. Instead of just having a lightbox with the tube in it, the tube is wrapped in a reflective material that focuses the light onto a diffusing plate, so I'll have to figure out how to focus the LEDs onto that...

I fortunately got a much better deal on mine, $5 at a thrift store. I'm thinking of getting a CF or PCMCIA sleeve for mine, to give it more memory and wireless, but I think I'd be better off putting the money towards something else.

[bacteria]

If you get any progress on the LED mod to the screen, please let me know as I might have a go too.

As I recall, the 3600 is the same as the 3660 except the 3660 has the extra memory.

$5! (I bought mine when it had just been released in the UK) - as I said, old obsolete and worthless; however it is as good as any other PDA out there; not as powerful and no GPS, etc; however fulfils its role as a good PDA.

I read about 5.1v from the mains pack; interesting you say 3.7v from the battery, I wonder how low it goes - will experiment with my TI card during the morning.

Nice little project - if you mod yours too, we can compare notes and help each other!

[bacteria]

Ok, I got the figure of 5.2v from testing the voltage from the PSU.

I tried 3 x AA batteries, about 3.7v as you suggested; it didn't boot. I made it 4 x AA at about 5.2v and it booted and worked fine.

I replaced the tiny tact switch membrane on the on/standby switch with a proper 12mm tact switch, works fine. Soldering has to be accurate!

The small mobo with the controls and power-in plugs can become slightly detached, so I was getting the initial boot screen, then a hazy orange scree or black screen. Once it booted up and gave an error, booted again and it was fine (phew, didn't corrupt the ROM chip or BIOS!). This PDA seems to take some abuse, however the solder points are so tiny it would be easy to introduce a short and fry the thing.

I tried to use my TI card I had, found a small resistor which output about 4.6v and rigged it up to 8 x AA's. Booted fine, but after a minute or so the screen died, pressing the on/standby button on the PDA brought it back, then same thing happened again. This wasn't good enough, so I put 4 x AA's in a 6 AA holder (and put a wire between two negative terminals to make it a 4 x AA holder as I don't have one at the moment). This gives 4.92v at the moment (slightly less than with the other batteries I had), system fine, booted up, left it for a while now (about 15 mins), screen still working, on full-bright screen setting; I want to see how long the batteries last for before they die and need recharging.

Interesting, with the TI card I got the power saying about 80% power; with the 4 x AA's the system thinks it is recharging the PDA battery, which of course it isn't as it was removed. Either this is the difference between 0.3v (seems unlikely) or the voltage the TI card was feeding it. Strange.



SITUATION: If the PDA loses power even for an instant, it loses all its settings, so it needs power at all the time.

QUESTIONS: (please reply, the outcome will influence this build):

* Would I be able to plug in the external power at the same time as the batteries are working or would it overload the system? I connected the batteries to the same power terminals as the mains connects into. (as per pic).

* If the above is ok, would that also keep the NiMH batteries recharged?

[bacteria]

Update - I can add to this as the time progresses:

Using 4 x AA batteries, 2700NiMH


Start - 0 hours @ 4.92v

After:

1.5 hours @ 4.78v

2 hours @ 4.75v

2.25 hours @ 4.73v

3 hours @ 4.62v

3.5 hours @ 4.39v - screen started to flicker every few seconds for a few minutes, then screen went off. PDA did turn on again ok, but clearly was at the base of its voltage range. Still, 3.5 hours of continuous use on highest light setting is certainly over double use life against what I used to get!

Test 2

Ok, I have now rigged up two sets of 4 x AA's, in parallel. They are still 2700NiMH batteries, and this time I have set the brightness of the PDA to high bright rather than super bright. With two sets of batteries in parallel, the brightness on high bright is similar to super bright with one set.

Let's take a guess what I will get - 7-8 hours?? (guess). Anyway, I will have to turn it off in a few hours anyway, can always resume test tomorrow.

Start - 0 hours @ 5.09v

After about 30 mins it decreased to about 4.93v, and has stayed there at about 4.91v-4.93v for the last 3.5 hours; and still going strong. This is encouraging...

After 4 hours, the voltage is 4.9v. I am leaving it overnight on standby; it will be interesting in the morning whether the voltage has remained, or decreased by much, being on standby. Because I have had to run batteries via the external power port, the system thinks it is recharging the battery which isn't there, so it may drain the batteries I am using. If, in the morning, I have about 4.9v still, there is no problem, if the batteries are drained, there is a problem (means the batteries must be connected to the mains during the night). Time will tell....

[vskid]

I realized why we were saying the battery was different voltages, we weren't talking about the same thing. You were talking about the 5v power input, I was talking about the battery itself, which is 3.7v (mines actually .1v its so dead).
Instead of trying to find a place on the board to solder the new batteries, I decided to just remove the battery from where it is soldered (see pic). This stroke of inspiration came while I was taking apart my laptop's secondary battery to try to replace the li-ion cells with NiMH's, and I realized that I could do the same for this.


I have homework to do right now, but I'll try powering it with NiMH's later and post my results.

[Skyone]

You might want to add in a coin battery backup, then.

[bicostp]

If it has an SD slot, put in the biggest one you can find and install the usual goodies:

- TCPMP
- Pocket GnuBoy
- Stella
- PocketVCS
etc.

I have to agree with you; PDAs are more than capable of playing games but their controls are HORRIBLE for gaming. I can't wait to see what becomes of this Frankenstein's monster of a handheld.

Are you going to make it upright like a Gameboy Color, or horizontal like a PSP?

[vskid]

If it has an SD slot

They don't.
There are sleeves for them that have CF or PCMCIA slots, I might get one if I even have the money and need for one.

I can't find more than 2 of our rechargeable AAs, so right now I'm testing it with a battery from another PDA (hasn't blown up yet).

[bacteria]

Hi guys, nice to see this thread is getting some interest, cool!

update on power: after system being on last night, with 2 sets of 4 x AA 2700NiMH cells in parallel, I turned it off at about 4.93v (the voltage fluctuates plus or minus about 0.02v all the time). After it being left on standby until the morning, about 9 hours later, the batteries registered (system on standby) at 4.95v, I turned system on and it reduced to only 4.85v.

It has been on for a further hour and a half (total of 5 hours testing plus overnight standby), still at 4.84v. A couple of times the screen went off, so I pressed the tact switch to turn the screen back on, then played on the PDA for a while, went through a number of system settings, adjusted the clock, etc. I think this switch off was due to a reported bug in the program on the PDA which sometimes does this after the clock goes midnight (it was showing as 2001 - I changed to the current date and the light has stayed on fine...).

Update: Screen stayed on since above (changing system date), been on for a further 30 mins (5.5 hours in total), still registering 4.83v.

Update 2: After system has been running in total for 7 hours, it is still at 4.8v. This is already 5x the life I used to get...

This is a slightly unfair test scenario after all, as you tend to take your PDA off standby to use it, then back on standby when you finish doing what you are doing; in reality, getting the figures I am getting at the moment, I could get several days worth of use from the battery packs.


Replies/Comments:

vskid - Yes, by battery was dead, and anyway, it didn't help that I cut a light slit in part of it getting those wretched screws off. I initially decided to try to hook up the new battery pack to the terminals, but couldn't find somewhere to solder too, so decided to scrape the traces on the ribbon; damaged the ribbon and couldn't get it to conduct as it didn't seem to be metal inside the ribbon. I couldn't find the positions on the plug the connectors went into, anyway, didn't matter as the joints were so minute they were too small to solder to anyway. That's why I used the other end - I want the system to be connected to my PC anyway for syncing data and copying programs to the PDA, so figured I would use the plug for the external power to connect my batteries into. That is why it needs more than the 3.7v you mentioned - at 4.39v the screen really isn't happy, goes into standby mode. Not really an issue.

I had expected the TI card to provide continuous power, doesn't look like it does (see earlier post), is this typical of them??

I would have thought if you manage to attach batteries to where they should go, and you only need 3.7v that perhaps 3 x AA's might be a stretch? You will only have about that to start with. It will be interesting to see if you run it on 3 batteries and if 4 works fine or fries the PDA.

The slot under the PDA for the plug-in - it is about 44mm long (outside to outside), will a CF card plug into this? It looks like it will, I Googled the dimensions and got "3.3mm x 36.4mm x 42.8mm (Thickness x Length x Width)", eg http://www.interfacebus.com/Design_Conn ... _Card.html

Skyone - sensible, but I can't do this for the reasons above, although I do have an alternative solution (see below).

bicostp - I can transfer games and applications to the PDA via the USB connection and the MS sync program. It doesn't use SD cards, but has a large connector under the system. The system stated it can back up to CF cards. I have put some watches on cheap 256Mb CF cards on e-bay - no point getting a larger capacity one as the PDA is only 64Mb (mine is the 3660 model with the extra memory (!)), and naturally if you buy a bigger capacity one they will cost more - I might get one of these CF cards for about £4 or so.

Yes, this PDA plays some emulations fine, as I remember, it played NES fullspeed, Megadrive ok but a bit slow - it was only 200Mhz, far slower than modern PDA's.

Yes, the controls are horrible on PDA's (and mobile phones too), that's why I figured on putting in proper tact switches and a D-pad, and a better speaker (I will keep it a small one, from the PSone screen). On the original PDA the D-pad (ish) was in the middle under the screen with two buttons on the side, I will probably keep this style, although will space them differently, so to answer this query, "GameBoy style".


The case:

In regards to the case, I want to make this as reasonably small as I can, no point making a brick! The mobos and screen by themselves give a footprint of about 147x75mm.

I thought about putting the 8 AA batteries in 2x2 on each side of the case, but I won't save any depth of the case as the screen and mobo itself are about 15mm deep (about the same as an AA battery) so two AA's on the sides would make a case of about 35mm-38mm deep or so, as would having the batteries in single file under the system; yet this means in this configuration that I can save width to just over the original PDA's, which is better.

I am aiming for the final sizes to be (including case) about 155x83x40mm. To give some comparison, the original PDA, without its docking (which I included above in my mod) was 129x83x18mm. This isn't enough of a difference to be bothered with, or reduce its usability or portability.


Thoughts:

In regards to the powering of the system, I thought I might try the following:

Situation: plug available for external power. Two sets of 4 x AA's, one set able to work for about 3.5 hours continuously, in parallel, massively longer.

Project: when the batteries start to get low, I can remove one set of AA's and replace them. During this process, the other set of AA's will keep the system powered. With the new set of batteries in place, I can remove the older set and replace them; no loss of power or data that way.

I am hoping someone will please answer this query I asked earlier - if I am running the two sets of batteries in parallel, and also plug in the external mains plug into the system too, would that extra amperage be likely to blow the system or just run happily and also keep the NiMH batteries charged?

If I don't get a reply, I might just take a chance and try it; I would try it firstly with the small mobo disconnected from the main mobo and if it registers about 5v still (as I would expect), would then plug that into the main mobo - if I don't get smoke and nothing fries, all is ok - it just seems a kill-or-cure decision - I just need to know if adding extra amps could damage the circuits or simply just provide an extra reserve of amps which aren't needed and don't have any ramifications. If I try this and fry the boards, project ends, so if you can provide advice that would be lovely please.

My intention is to basically keep the PDA plugged in most of the time to the mains anyway, however I want to make the system mobile (batteries) and also not die if we get a powercut (as happens sometimes).

[bacteria]

4.77v @ 7.5 hours.

Decided to get back to my GBA briefcase mod in the interim. When the batteries finally drain I will get back to this mod again; I want to rewire some of the buttons into tact switches.

[bacteria]

Final figures:

4.73v @ 8.5 hours
4.67v @ 9 hours
4.64v @ 9.5 hours
4.54v @ 10.25 hours

at about 10.5 hours the voltage dropped to about 4.49v and the PDA went into standby mode. Still, 10.5 hours with two sets in parallel instead of 3.5 hours with one set; quite a difference! This is a lot, more than enough for a day's solid work use, without having to worry about the battery power getting too low (as I used to have to think).

I then changed one set of batteries, then the other, all fine, even though the voltage in both packs are higher this time at 5.5v with a fresh set of batteries (phew - however I had to check this).

Although I got 10.5 hours on batteries I charged a while ago, I could probably get about 12 hours use from a freshly recharged set.

Checked with my Father who used to do electronics, he concurred that what I was aiming at should work, ie:

* Putting the mains power in whilst the batteries are working shouldn't blow the system as the battery voltage is the same/higher than the mains power and there is no implication with adding more amperage.

* Having the mains and batteries working at the same time should run the system and also recharge the batteries; in practice however, the batteries can be disconnected manually by a switch when not needed, if I know I may be using the PDA away from the mains the next day I turn the batteries on and the mains will recharge them, ready for use.

[bacteria]

Yes, the battery and recharger scenario works, just tried it. I plugged in the mains along with the batteries, removed the batteries, all fine, connected the batteries again and removed the mains power; all fine; as expected.

Project is making nice progress, I will be able to do what I want to achieve with this project, as long as I don't make any mistakes with my soldering.

[vskid]

SUCCESS!!!

I got it running on 3 NiMH AAs. The paper is between the mainboard and the alligator clips on the battery ribbon so they wouldn't short on anything. It said it was charging them when I plugged it in, I have it running them down right now to see if it really will charge them.

The light tube is surrounded reflective material, with a small slit along the side where it met the glass in the screen. I think its front-lit, thats what a site said, and it glares the same as other front-lit things like the GBA SP when at an angle. I must figure out how to LED mod it, its hard to see the screen with the florescent lightbulb I have in my room.



All I did to remove the battery from the ribbon was put a hot soldering iron on the connection and it almost instantly disconnected. Then all I have to do is put an alligator clip on each. The right square patch is positive, the left is ground/negative. I wanted to use the original batteries power points so that I could charge the batteries with it.


This is the connector bacteria was talking about. It plugs into sleeves, but it might have all the required pins. The sleeves are $30+ on ebay, if someone has one, I bet we could figure out the pinout.



I'm going to try to find a point to power the LED mod from. LED modding it is pretty much my main priority now that I've got the batteries (hopefully) figured out.