Jornada 680 not booting + faint green recording LED

I've tried to load "/Windows/default.htm" into PocketWord and it crashed the whole system.
Now when I try booting it up, it sometimes produces a corrupted screen (boot logo, etc) or a TLB/other exception error, offers to reset the RAM and so on.
I'm trying to reset the RAM by removing the main and RAM batteries now - how long should I wait?

The most interesting thing that happens, though, is that the recording LED (on the front of the device), the one that's supposed to light up red when you're using the voice recorder application,
glows faint green (with occasional flashes) - WTF?


Is my RAM dead?
Leaving it without power for ~10 minutes as recommended in the boot message didn't work, should I try again for more time?

EDIT: Along with the error messages on boot, it also sometimes produces an "Exiting backup mode" along that.
EDIT 2: I've found out that holding any key on the keyboard while powering it on makes it consistently appear to boot (it's even loaded WinCE two times now), but that's still very unstable.
Could that effect be caused by the pressure that I apply to the keyboard? I've read that the RAM/ROM module is located under that so it not making proper contact with the motherboard connector could actually be an explanation.

Edited by SopaXorzTaker 2018-01-23 12:12 PM

UPDATE!

So I've decided to take it apart to try wiggling the RAM, etc.
With no illustrated instructuons available anywhere (I've even found this: http://repair4pda.org/disassembly_hp_compaq.html, but the link to the actual disassembly instructions was dead and the archived copy at web.archive.org didn't contain any images).

I figured it out myself (basically unscrewing everything I could, noting the length of each screw, until I noticed that the keyboard has fallen out )

I've quickly identified the RAM (a daughterboard on the left under the keyboard if viewing the device in normal, working orientation, with the screen open).

After reseating it, my Jornada appeared to work fine, but promptly crashed, with nice loud noise coming out of the speaker.
I've figured out that the contact wasn't so good and added a small spacer made of sticky tape - and it works just fine now!

Does anyone know any kind of a memory test utility for HPCs (I want to make sure it works properly)?

EDIT: whoops, it's crashing again - but it's clearly because of that RAM connection, maybe I'll try cleaning the contacts then.

Edited by SopaXorzTaker 2018-01-23 2:16 PM

The way the OS works is that it simply reports what amount of RAM is available...period. Since applications are loaded into available memory byte by byte sequentially...and not fragmented over the storage area such as you would have with a memory card...it really isn't an issue. Either it works or it doesn't. Ideally you should be able to go to the control panel after a hard reset and check the available amount of memory...it would be the same for every J680.

You discovered your problem...and I think that is probably all you need to do is fix that. A good can of spray contact cleaner can work miracles with oxidated contacts.

I've meant a tool such as Memtest86+ (available only on PC) for checking the correct operation of the RAM - e.g. stuck bits, etc.
By the way, I've found out that the two NEC chips on the daughterboard are actually ROM and that the RAM is actually two IBM chips that are mounted on the mainboard underneath.

I'm not so sure about the problem anymore, as the RAM is mounted on the motherboard (so the contact must have been good), but the intermittent faults were also altering the framebuffer, which should be contained in the onboard RAM.
Maybe the intermittent contact of the ROM module is producing errors on the memory bus (it's shared between the RAM and the ROM, it seems)?

Just tear it down and check all the connection… ribbon cable… etc…

You mean tearing it down completely?
I'll try that later - I'm not sure why a seemingly completely unrelated connector can affect the device, but why not try?

Edited by SopaXorzTaker 2018-01-25 4:44 PM

I did disassemble it and reconnect all of the ribbon cables, but unfortunately this didn't help: https://www.hpcfactor.com/forums/forums/thread-view.asp?tid=18446.