Trying to reverse engineer a Palm IIIx--can't figure out the up/down buttons!!

Hi,

Yeah, I know the Palm IIIx is kinda old, but...I want to overwrite the OS (already have my own little piece of firmware in flash), and would really like to make use of the up/down buttons. (I know the other 4 buttons are input to Port D, D0-D3).

I looked at all the gpio (parallel port) inputs and can't find any handling those two buttons. I looked through the POSE source code and saw reference to keyboard rows & columns, so I thought they were multiplexing (banking) the 4 gpio lines. So, I inverted the output of all the gpio output bits (using the small ROM debug monitor) and then checked Port D. Nothing. I then saw in POSE a reference to HW ID bits that may also be multiplexed. Geesh, that means finding two (or more) combinations of gpio outputs and getting them in the right combination--IF that's a correct assumption in the first place...

So, I decided to try a long shot and ask the internet community. Who knows, I might get lucky and one of the developers will take pity on me. :)

So, if anyone has any info on those two buttons and how the firmware reads them, I'd be much obliged.

Thanks,

Jim

Reply to
Jim
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I thought the IIIx had MASKED ROM and can not be flashed?

Maybe I'm thinking of the IIIxe, hard to remember 10-11 years ago anymore.

Reply to
Jim Anderson

I still use my Palm IIIc daily. Still have my Palm IIIxe as a backup. Even lugging around the folding keyboard, it sure beats lugging around my laptop. ;-)

--
Bill
Reply to
BillW50

Your not the only one. I still have/use my Palm IIIxe. I haven't needed a new one yet... :)

Reply to
gene martinez

I moved to a samsung sph-i500 (palm os4) which I finally retired a couple of months ago when the case literally disintigrated on me. Bit of plastic started falling off. The paint had worn off 18 months prior and the case must have finally developed stress fractures.

I moved to a palm centro (palmos5) in a stop gap move. I'm not ready to move to AT&T crappy network to use an I-Phone, and really don't want to use a windows mobile and insane resource requirements, dog slow performance and frequent lockups and crashes. Maybe by the time it falls apart on me, there be better solutions in the marketplace.

Reply to
AZ Nomad

I've still got my IIIx but I don't use it any more. I replaced it with a Zire 31 that I use all the time. The only drawback is that it needs recharging more often than the IIIx which I used with NiMH cells.

Leon

Reply to
Leon

Well, I got busy and didn't get a chance to work on my project until today. I was sooo excited when I saw a bunch of people responded to my question!! Unfortunately, no one answered it. :( Oh well, at least I brought people down memory lane. :

FYI: the IIIx does have flash. I already re-programmed it. It's now running a simple little program I wrote. I still don't quite understand the bootup process though--when I put batteries in it won't run--I have to hit the power or reset button.

Anyways, I'll probably ALWAYS be interested in knowing how to read the up/down buttons, so if someone years later reads this and knows, please send me an email.

Thanks much everyone!

Jim

Reply to
Jim

More than a stroll down memory lane. I thought I had a Palm III, but on looking harder at it I realize that it is a Palm Pilot Pro. Even though I have upgraded the OS to ver 2.0 Pro, but even software that says it will run under v2.0 won't run on this and will even tell me to "upgrade" to 2.0.

I want to use this device for geocaching. I have a Zire 72, but the case is just not as easy to hold and does not feel as rugged. I really like the squared off, plastic case and the fact that I can see the screen under *any* conditions.

I wonder how many of these things are still floating around?

Reply to
rickman

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