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Upgrading/repairing C128

I thought I should have opened my C128 several months ago when I bought it, to check exactly what upgrades have been fitted to it, as well as if there's any space to fit any more upgrades, but I haven't.

Unfortunately, a good reason to open up the case soon is that the left hand SHIFT key suddenly stopped working during a late night programming session.

From what I see and have been told, this is a German model C128, meaning a “doorstep” model with a German keyboard, and a separate disk drive. It has had the VDC 64K upgrade fitted, as well as an extra ROM containing various utilities programmed by a C128 enthusiast, which is called a “Servant ROM”. I can copy disks using one of these utilities, which makes use of all installed RAM. This means that it can read the whole disk contents into RAM, before writing it to another disk, without any further disk swapping.

There are some upgrades for sale on eBay, but I don't know if I have anywhere left to plug them in. One of these is http://www.ebay.co.uk/itm/Commodore-128-GEOS-128-v2-1581-/131172715610?p... , but I may not be able to plug this in, unless I remove my “Servant ROM”. Unfortunately, I used this item just as an example, because my disk drive is one of the 1541 models, so that ROM probably wouldn't work anyway. Another item is http://www.ebay.co.uk/itm/Commodore-128-Basic-8-video-utilities-rom-chip... . There are also adaptors, such as http://www.ebay.co.uk/itm/Commodore-128-Kernal-ROM-Adapter-/131172715630... , which seem to supply more sockets for upgrades, but I'm not sure what they'd work with. I think I'll also ask the sellers of these items, but it's best to ask for advice on this forum.

 

 

Re: Upgrading/repairig C128

Paul Alba wrote:

> There are some upgrades for sale on eBay, but I don't know if I have anywhere left to plug them in.

Other than the unused ROM socket in the C128, the other plug-in possibilities are ordinarily the user, serial, expansion, and even the cassette port.

> One of these is http://www.ebay.co.uk/itm/Commodore-128-GEOS-128-v2-1581-/131172715610?p... , but I may not be able to plug this in, unless I remove my “Servant ROM”

That's correct.

> Another item is http://www.ebay.co.uk/itm/Commodore-128-Basic-8-video-utilities-rom-chip... .

Yes, that is the WalrusSoft software of Basic 8 which has been burned to an EPROM.

> There are also adaptors, such as http://www.ebay.co.uk/itm/Commodore-128-Kernal-ROM-Adapter-/131172715630... , which seem to supply more sockets for upgrades,
> but I'm not sure what they'd work with.

That's from Tim Harris, but its use is limited, because I can only think of two kernals for the C128 - the original ROM in the flat C128 and the upgrade ROM which you could install in a flat C128 or plastic C128D and which came standard in the metal C128DCR.

A nice upgrade is the Megabit ROM adapter. It fits into the unused socket of the C128 or C128D/CR, and contains many utilities, productivity titles, and even a few games. See the thread at http://www.commodore128.org/index.php?topic=2645.0

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

So it seems I can't fit any

So it seems I can't fit any of the items I listed unless I remove my Servant ROM! Another possibility is some kind of ROM switcher for the unused ROM socket. I assume from what you said that the Kernal ROM adapter won't fit this socket.
 
As for the Megabit ROM adapter, I'd have to remove my Servant ROM, so I'd have to be sure it was a better replacement. One of the menu items is actually called Servant, so does that means it includes what I've already got? The manual is on http://www.scribd.com/doc/4711978/The-Servant-for-the-Commodore-128
 
That Megabit topic was posted years ago, but some more recent publicity is on http://www.n8ie.com/c64er/megabit.htm , where the screenshots show that it's compatible with the 40 column mode, although the review in the original topic seems to say that it's for 80 column mode only.
 
 I'd appreciate it if someone would post some pics showing a C128 motherboard with and without an extra ROM chip, as well as with and without the VDC 64K upgrade, so I can see what I'm looking for. 

--

Paul Alba

Re: So it seems I can't fit any

Paul Alba wrote:

> Unlike the Amiga 500/2000/600 computers,

I have never seen a ROM switcher board for the C128. There is a definite lack of space to put one in the area of the C128 unused ROM socket.

> I assume from what you said that the Kernal ROM adapter won't fit this socket.

Right. Tim Harris' Kernal ROM adapter is for the Kernal ROM socket, not the unused socket.

> One of the menu items is actually called Servant, so does that means it includes what I've already got?

Yes, the Servant in the Megabit ROM adapter is the same Servant in your standalone chip.

> where the screenshots show that it's compatible with the 40 column mode, although the review in the original topic seems to say that it's for 80 column mode only.

Some of the programs in the Megabit ROM adapter are 40-column (like the games), and some are 80-column (like Vizastar 128 and Vizawrite 128).

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

Good news! My left hand SHIFT

Good news! My left hand SHIFT key has suddenly started working again.

--

Paul Alba

Re: Good news! My left hand SHIFT

Paul Alba wrote:

> My left hand SHIFT key has suddenly started working again.

Hmm, maybe something was stuck under it and then got jarred loose.

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

Don't take for granted having

Don't take for granted having the finger available to operate the left hand shift key.  >:)
(lost my ring finger last year in a bizarre accident)

I think if I lost it, or in

I think if I lost it, or in your case, it could be replaced by biohacking or a cybernetic implant. I could use my first OR second finger, anyway.

--

Paul Alba

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