Commodore 128D - need help!

[Darrin]

Hi guys,

I managed to win a mint condition C128D off eBay.  The thing looks like it is almost brand new, whoever owned it looked after it like a baby.  It came with the manuals, disks plus some extra floppies and cartridges.

However, I have a problem.  The RF out works perfectly.  I have a C64 video-composite cable that only seems to produce monocrome images and when used on the C128D it produces rock-steady monocrome images in C128 and C64 mode.

I have a C64-S-video cable which I've used successfully with my C64C (until I got the Chameleon and used the VGA out) and I get this:

C128 Mode:  Distortion at the top of the screen.  Image moved to the left.


C64 Mode:  Perfect!


Does anybody know what might be causing this?  Does the C128 not like the s-video cable?  Is there something wrong with a chip?

The workaround is to simply use the RF output when using C128 mode, but it is annoying.

Also, is there anything that takes the RGBi of the C128/C128D and allows it to be connected to a VGA port?   I wouldn't mind being able to access 80 column mode.

Thanks in advance.

Darrin

[Darrin]

Darn

What does the 80 column output look like?

I am not a commodore 128 expert, I do have a 128d, but I am guessing that this is interference of some sort, a bad Cap or bad video cable.

No idea on the 80 column as I don't have a RGBi cable (or monitor).

I had to go on another trip so I can't fiddle with it at the moment.  When I get home, unless someone comes up with any solutions, I'll test the same s-video cable with a regular C128.

I guess it wouldn't do any harm to open her up and check for anything leaking or loose.

[Darrin]

You really need an 80 column monitor! That's were the 128 shines.
I have never this problem before - But I have never used S-video from a 128D.
PS - I may know where you could pick up something like a 1902 for a very fair price - not all that far from you....

Really?  Please tell me.  I'd be interested.

Thanks.

[Darrin]

Do you have a 1084 lying around (i bet you do)?  Hook up the 128D 80 column output up to the RGBI input on it (the only problem is finding a cable).

I'm older than that.  ;-)

Unfortunately my A1081 died a couple of years ago so all of my connected Amigas now have some sort of scan doubler fitted instead.  VGA monitors all around I'm afraid.

Two of the monitors have the 3 RCA type (RGB) component inputs, if they're any use.

[Darrin]

Darn

The TTL RGB would have worked on the A1081.

I think that some of the old CGA monitors out there would work.  There may be some on ebay.  They would need the ability to do RGBI.

I'll see what Motrucker has up his sleeve.  This may be interesting.  

[Darrin]

Don't need one if you can live with monochrome video. Pin 7 on the RGBi port is monochrome composite video. Pin 1 is ground.

Interesting.  Thanks for that.  I might try and bodge a cable just to look.  It should be OK for CPM.

[Darrin]

@Darrin

Now that you have a commodore 128d, would you like the chameleon 64 to work with it?

It would be nice, but the existing Chameleon64 will not (and supposedly never will) work with the C128 without a redesign.

While I'd rather have mine plugged into a C128 than my C64C (mainly for the keypad), I'm honestly more than happy with it as it is.  Besides, there is always the possibility that someone might port a C128 core.  Imagine having a C64 boot into C128 mode instead of the other way around.  

[Darrin]

Who would do it?

Truly,
Robert Bernardo
Fresno Commodore User Group
http://videocam.net.au/fcug

Anybody who wishes to.  That's the beauty of the FPGA cores.  

[Darrin]

I made one of the monochrome cables for my 128 before I got my 1902 monitor, and it works fine.  I used it with CPM, and didn't have any problems.  I am not sure what monitors will work with the 128, as it has the digital RGB output, but I know the 1902 does, as that is what I use.  I also have made one of the S-video cables for mine and have it hooked to a small LCD TV for 40 column use.  It works fine as well.  I know this isn't much help, but just thought I would add my experiences to the mix.  If I can help with testing or anything, let me know.

Jeff

Thanks Jeff.  It confirms that the C128 works with the s-video cable, so it must be an issue with my C128D signal in C128 mode or my TV/Monitor.  

[Darrin]

I have a friend in Florida, who still a small amount of 8 bit stuff (used to be a re-seller) I will call him this evening to see if he has a monitor left.
This way shipping should not to bad?

Great.  Thanks.  Please let me know what he says.