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zlasher
December 4th, 2010, 07:01 AM
Hi guys! This is my first post on this forum..

I've recently rescued a Tiki 100 stored in a open car-port for the last couple of years..
The boxes was totally ruined, the monitor however was in a plastic bag, and works great. The computer itself was not stored in a additional bag, and as temperature here go from +20c in the summer to -20c in the winter, this is not optimum storage for any computer.

After I picked it up, i cleaned it carefully, and it actually worked!
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After a while it stopped working, and i had to investigate a bit further. I found this IC had actually dissolved after I received it (yes - you can see rust in there!)
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Luckily I have a complete documentation, and have ordered a replacement IC.
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There is always a risk of the whole thing rusting away - so if anyone has a tip how to avoid this I'd be glad to have any tips - I don't know if a thorugh cleaning will avoid this - or make it even worse..

per
December 4th, 2010, 07:15 AM
Nice.

I have a (Kon)Tiki-100 myself, but I don't have anything extra besides an analog/digital interface card and one disk of "Verdensgeografi". Does any of the manuals include a chapter on the analog/digital interface expansion-card?

I hope you'll get it working again. The 74LS240 shouldn't be that hard to obtain (as you state), and I believe the most difficult part will be to desolder the old IC.

What version is the internal ROM, and what software do you got for it?

Chuckster_in_Jax
December 4th, 2010, 08:52 AM
Great to see you could save it. Good luck with the repairs. I don't remember ever seeing one of those here in the US.

zlasher
December 4th, 2010, 09:00 AM
I don't really know the rom version as of now - I'll try to find it out when (/if) I get it up and running again..
Only clue I see is a chip marked with a pen - it says TM 2.03 W and another marked V (or U) 41.

I've got a bunch of software for it..

Supercalc 2 boxed orgininal.
Tiki Invaders, a few other games
Master Catalogue
Basic (and a few other languages)
Turbo Pascal
Aztec C-Compiler
AC80 C-Compiler
Macro-80 Assembler
Wordstar
Spreadsheet
Vista

And some disks I don't really remember what contained..

There is also some com utilities made by the previous owner. Even though it was stored a bit exposed the last few years, the computer really meant something special for him - as he didn't just throw it away..

Great to finally find a forum with other Tiki owners aswell - it's really sad they where all just thrown away after the schools where finished using them - we should've taken them off their hands back then..

per
December 4th, 2010, 09:37 AM
It would be really great if you are able to image those disks as raw disk images. It should be easy enough, as the format is 1 or 2 heads, 40 tracks, and 10 sectors. If you got a PC with both 3.5" and 5.25" drives, Mike's dskimage (http://www.brutman.com/PCjr/pcjr_downloads.html) should do.

ROM version 2.03W is the more recent version which supports double sided disks. My system has the earlier 1.30 ROM which only supports single sided disks.

saundby
December 5th, 2010, 09:46 PM
What a beautiful machine! I love the keyboard.

zlasher
December 6th, 2010, 10:12 AM
It would be really great if you are able to image those disks as raw disk images. It should be easy enough, as the format is 1 or 2 heads, 40 tracks, and 10 sectors.

Are you sure about the sectors/tracks?.. I've tried dskimage a couple of times now - but I'm unable to make any images..
As the Tiki is down, and I can't find my old 5.25" floppy drive - I tried moving the Tiki drive to an old PC.. It lights up as it's supposed to.. but all I get is "0x02 address mark not found"..

Any tips?

Hmm.. Might be that the drives are not really compatible with my new(er) bios.. I'll have to do some more testing here..

per
December 6th, 2010, 10:18 AM
Are you sure about the sectors/tracks?.. I've tried dskimage a couple of times now - but I'm unable to make any images..
As the Tiki is down, and I can't find my old 5.25" floppy drive - I tried moving the Tiki drive to an old PC.. It lights up as it's supposed to.. but all I get is "0x02 address mark not found"..

Any tips?

Did you set the drive-type to 360KB in BIOS, or did you set it to 1.2MB? Those drives are only double density, and won't work if set as 1.2MB.

zlasher
December 10th, 2010, 12:11 AM
It's hard to find bios'es anylonger with support for 360kb - and still supporting USB/memory cards to ease copying data..
I only have a couple of really vintage PC's, as I mostly collect other platforms.. (consoles or commodores/sinclair)..
I'm working on this, trying to get it working.. I'd love to share the applications I have available..

carlsson
December 10th, 2010, 01:14 AM
As a side note, I bought a second hand AM2 socket motherboard in January 2010. Its BIOS had an option for a 360K 5.25" drive, not required on the machine it went into but still something that caught my attention.

zlasher
December 26th, 2010, 04:45 AM
I've scanned the original technical documentation for the Kontiki-100 system.
The doc is in Norwegian, I guess this is mostly interesting to scandinavian collectors anyway. The list of components and other parts of the doc should be easily understandable by anyone.

(filesize = 66Mb)
pdf (http://xboxlinux.mine.nu/tiki/tiki-system.pdf)
zip (http://xboxlinux.mine.nu/tiki/tiki-system.zip)

zlasher
December 31st, 2010, 09:22 AM
I've completed the installation of the replacement IC - unfortunately still the same error during power-on.. The graphics key start blinking just after the floppies have been powered..
The IC I've replaced I think is connected to the floppy drives.
Any suggestions are welcome :-)
For now I'm using a magnifying glass and examining every inch of the motherboard for clues, it takes a long time, and I don't know if the error is visible to the human eye.. (as the first IC was)..

RickNel
December 31st, 2010, 01:47 PM
I would be checking all capacitors (especially tantalums), starting with those near to voltage regulators and then those in any place you are suspicious about, like the floppy drive interface. Since you have some visible corrosion, I would also be giving any other capacitors or resistors a gentle poke with a small screwdriver to see if they move or crumble. Sometimes metals or other materials in these components have decayed without the damage being visible, and this can produce all kinds of effects that may show up when the components get warm after a long cold storage. The fault may not be in a logic chip.

I haven't downloaded the 66Mb docs- does your documentation include full schematics? It is easier to track down suspicious areas of the board if you can check what each component is supposed to be doing.

Good luck
Rick

zlasher
January 1st, 2011, 02:53 AM
Thanks for the hint, I'll examine the capacitors you mention.
The docs include a full schematics (at least I beleive they do) - It's a bit to complex for me though, but you might get more out of them than me :-).
The docs also includes a layout of the motherboard, I've replaced IC U31 (LS 240).

Thanks for the tips!

per
January 1st, 2011, 03:15 AM
Thanks for the hint, I'll examine the capacitors you mention.
The docs include a full schematics (at least I beleive they do) - It's a bit to complex for me though, but you might get more out of them than me :-).
The docs also includes a layout of the motherboard, I've replaced IC U31 (LS 240).

Thanks for the tips!

You may also want an oscillioscope.

The first thing I would try is to figure out what works and what does not works, based on the block diagram from the documentation. You say that the system gets as far as checking the floppy drives, which means that the main memory and the control logic should work. As of I have understood, the problem you describe is that the cursor blinks on the monitor, but no text appears. If this is the problem, you should definitively start by checking the control lines of the video-RAM. You should also check that the page-decode ROM (the small socketed IC with V/U 41 written on it) makes proper contact with it's socket.

zlasher
January 1st, 2011, 05:13 AM
Here's a couple of pics of what happens.. (to clear things up)..
The screen shows lines/garbage.. (no visible cursor).
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The keyboard indicator lights (lock and hjelp) lights up - the grafikk (graphics) key blinks, and the floppy drives (both) has a solid light.
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There is a light high pitch sound - I'm having trouble locating it, as far as I know it is not from the powersupply itself.
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None of the PSU components are getting especially hot, and no burns are visible..

Just noted this on the powersupply.. (superzoom!)
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per
January 1st, 2011, 05:37 AM
Ok. Then I definely would check the graphics logic first. It seems to V-sync properly since the entire monitor is filled with lines, but the video RAM may be malfuncting. The fitst thing you should do is to "reseat" any socketed IC, and if that don't help, you should try to probe the /CS /RE /WE of the video RAM.

zlasher
January 1st, 2011, 05:43 AM
I'll do that.. I've misplaced my IC "remover" - so I've ordered a new one, I won't take the risk of damaging any IC's as I remove them..
Thanks a lot for the tips guys! :-)

per
January 1st, 2011, 05:57 AM
I'll do that.. I've misplaced my IC "remover" - so I've ordered a new one, I won't take the risk of damaging any IC's as I remove them..
Thanks a lot for the tips guys! :-)

I always use a small flat-bladed screwdrive, but I agree that it is safer to use a proper IC removal tool.

RickNel
January 1st, 2011, 12:38 PM
I wouldn't worry about that slightly chipped component on the PSU. It's a rectifying diode and the fact that you are getting a video display shows that the PSU is performing acceptably, so that diode must be working OK.

The "high pitch sound" would be most expected to come from the monitor itself, if it is near the top of audible pitch. Otherwise it is most likely from a transformer somewhere. The sound waves are only created where a magnetic field is influencing some nearby metal that can vibrate. You can sometimes locate it by touching components with a non-conductive prod (plastic or wood) and noticing if the sound changes or stops. But don't prod around the CRT itself unless you enjoy hign-voltage shocks ;)

knutrl
May 12th, 2011, 05:30 AM
Thanks for the system manual... (did post some questions as a new thread)

Knut

Tor
May 12th, 2011, 06:23 AM
Ah, a thread I hadn't seen before you woke it up.. nice. I don't know why I didn't buy a Tiki system back then, after all I was a CP/M guy at the time. I was probably even more out of money than I remember.
And it had a Tandberg Data keyboard.. I love those. Didn't remember that either, until I saw the pictures.