Strange trackball/keypad issue

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Hi there!

I bought a damaged G1 from ebay to hack on.
There is some strange behaviour, that seems to be related to the trackball.
Everytime i scroll some pages for a while, the trackball is going really mad.
It toggles between applications, e.g. starts phone app or contacts and enters weird numbers.
If i leave it completely untouched the system behaves normal.
Just to give it a try, i disassembled the device and removed the trackball mechanic. Result: Everything behaves normal.

Due to these problems, i started a little research on the trackball parts.
So here's what i found (see attachment).

I will do some further investgation and check out if i'm able to fix this issue.
My suspicion is, that one of the magnetic sensors got damaged and toggles between high and low all the time, even without the trackball beeing moved.

Did anyone realized such a behaviour on a G1?
Any comments are welcome!!

Regards,

scholbert

Note that the trackball on HTC DREAM is identical to the trackball used in RIM cripplephones, so you can find a replacement easily... you can probably get a broken RIMjunk for $5 with good trackball hardware, or you can try at something like blackberrytrackball.com.

Hey lbcoder,

i knew that the touchball is identical to those used in the blackberries.
Thanks anyway to add this info and for pointing me at the web link!
Got a spare part with broken flat cable from another G1 device.
I'll have to do some further testing and then start the soldering job

BTW the trackball itself is not the damaged part. It's one of the magnetic sensor parts, i suppose.
Would be interesting if anyone else ever was affected by some irritating trackball issues?

Regards,

scholbert

It *is* magnetic though, so theoretically it *could* be an issue with the mechanical components rather than with the sensor itself... i.e. something stuck in the wrong place getting picked up by the sensor as continuous. Unless you've tried swapping them out already.

If you haven't already, I would at least try that. No need to go all the way to soldering just to find that it was something else

...
If you haven't already, I would at least try that. No need to go all the way to soldering just to find that it was something else

Sure, just did some test with the other mainboard (connector for touchscreen is damaged on this part).
The trackball behaves normal with this combination.
So the sub-PCB must be O.K.
I'll try searching for something weird on the original mainboard.
Damn, this would be much harder to fix i suppose

I'll keep you informed!
Anyway, maybe the datasheet would be of any use for the curious geeks

Best regards,

scholbert

experts welcome

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Hi again,

after some more testing and examination of the hardware stuff, i'm in doubt that this problem is hardware related.
So i started to think of some software related issues.
I know that bootcode and Android filesystem should be aware of bad blocks in NAND memory.
But anyway here's the history of the device (so far i know it):
- It came to me with stock bootloader and firmware 1.5
- A stock update was made to firmware 1.6
- I did a downgrade to RC7 using a goldcard
- Rooted the device using telnet
- Installed cm-recovery-1.4
- Followed the steps from cyanogen's wiki to move to v4.2.12.2
http://wiki.cyanogenmod.com/index.ph...to_CyanogenMod
- Also did a radio update to 2.22.19.26i
- Installed Hard-SPL as well

Everthing went fine, also no problems during registering to a google account.
I am able to boot into HSPL and the cm recobery is also intact.

It's very strange that the trackball weirdness did not change during all these up/downgrades.
I also got some issues with the power button.
Sometimes the device can not be set to sleep and immediately comes back into active state
Apart from that the device behaves quite normal...

What the hell is wrong with this device?
Could there still be some corrupt areas in NAND caused by bad blocks even after reflashing the system?
Any advice would be welcome!

Regards,

scholbert

Originally Posted by scholbert

Would be interesting if anyone else ever was affected by some irritating trackball issues?

Yes, my trackball likes to 'triple-click', which causes issues sometimes, especially when submitting web forms. I even have to use Ra_mon recovery over cyan because he has option to use talk button where my trackball multi-clicking would bypass the 'click home to continue any other key to abort' by auto-clicking to abort.

Hi jalsing,

thanks for your reply

Yes, my trackball likes to 'triple-click', which causes issues sometimes, especially when submitting web forms. I even have to use Ra_mon recovery over cyan because he has option to use talk button where my trackball multi-clicking would bypass the 'click home to continue any other key to abort' by auto-clicking to abort.

Sounds like hardware related damage, because this occurs in recovery mode as well. Maybe the pushbutton underneath the trackball causes this issue, while pressed.
Could be some corrosion or similar causing this...

Is there anyone who made some experience with file corruption or bad blocks?

Regards,

scholbert

Originally Posted by scholbert

I also got some issues with the power button.
Sometimes the device can not be set to sleep and immediately comes back into active state

I have noticed some weirdness in the power button, but I am thoroughly convinced that, at least in my case, it must be hardware related.... if I just shove down on the power button with the pad of my finger, it goes off and then right back to the lock screen. If I press the power button on the 9-clock point with a finger nail, it behaves as expected.

Although I must admit that this appeared coincidentally with a radio firmware upgrade.

Hey there,

I have been having an odd issue too although one that has not been mentioned. About a week ago when i scrolled "left" or while landscape "down" the trackball got jammed every 3 rotations. When you continue scrolling it repairs itself temporarily and then returns. This issue is still present but is not quite so bad.

I'm guessing that this would also be a hardware issue. Its not at a stage where its overbearingly annoying yet, just wondering if anyone else has similar issues.