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C-128 VDC RAM upgrade

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I recently added more RAM to my C-128's video memory, taking it from 16Kb to 64Kb. Rather than use the old method of taking out the existing RAM chips and adding new, bigger chips I opted for PCB that was first released years ago. These are a no solder option. The video chip is removed, this board pressed into it's socket, then the chip replaced in the board. One source of these boards is from an ebay seller, who is also active on www.lemon64.com

This upgrade can be used by GEOS, Maverick, and Super Snapshot, plus several graphics and DTP programs.

http://www.ebay.com/itm/Commodore-128-64k-VDC-Plug-Upgrade-No-Soldering-needed-/380985152237?hash=item58b47c12ed

This upgrade makes the C-128 just like the C-128D(CR). The extra RAM can come handy with the programs I mentioned.

 

 

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I have wondered about these cards. They look well made and I highly recommend the 64k RAM upgrade for anyone with the C128.

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Generally all metal box 128D has 64k RAM built in. There's a one line command to check for 16k/64k RAM:

Type this line in 80 column mode:

POKE DEC("D600"),28:POKE DEC("D601"),63:SYS DEC("FF62"):SCNCLR <RETURN>

If the screen looks normal and says READY, and all that, you've got 64K
display memory. If the screen is full of 0's and looks like a programming
nightmare, you've got 16K (just hit Stop/Restore and let Mr. Kernel fix it).

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Generally all metal box 128D has 64k RAM built in. There's a one line command to check for 16k/64k RAM:

Type this line in 80 column mode:

POKE DEC("D600"),28:POKE DEC("D601"),63:SYS DEC("FF62"):SCNCLR <RETURN>

If the screen looks normal and says READY, and all that, you've got 64K

display memory. If the screen is full of 0's and looks like a programming

nightmare, you've got 16K (just hit Stop/Restore and let Mr. Kernel fix it).

Right. The C-128 model, or flat 128, only had 16Kb of video RAM, but the C-128Dcr came with 64Kb of video RAM. It's a shame Commodore didn't put 64Kb in all of the 128s.

http://www.oldcomputers.net/c128d.html

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I used to have a flat 128 that had the 64K upgrade done by the previous owner. I found it handy in a few of the functions in the Servant 128 chip, too (I can't remember which, though).

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This upgrade makes the C-128 just like the C-128D(CR). The extra RAM can come handy with the programs I mentioned.

Thanks for the heads up! I also ordered their Jiffy DOS kit for my 128 to speed up my uIEC/SD.

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I think the original 16k was money issue. RAM were pretty expensive back then and CBM probably thought users would be fine with paltry 16k ram but decided for some unknown reason 64k was worthwhile upgrade when they tweaked the 128 to have built in disk drive and make it all in one box.

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7800fan wrote:

 

> ...CBM probably thought users would be fine with paltry 16k ram but decided for some unknown reason 64k was worthwhile upgrade when they tweaked the 128 to have built in disk drive

> and make it all in one box.

 

Well, the plastic C128D was an all-in-one box, but it still had the 16K of video RAM. The metal C128DCR was the all-in-one box that had the 64K of video RAM.

 

Truly,

Robert Bernardo

Fresno Commodore User Group

http://www.dickestel.com/fcug.htm

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I have wondered about these cards. They look well made and I highly recommend the 64k RAM upgrade for anyone with the C128.

The PCB I used was an older CLD (Chip Level Designs) bought from a seller named Freeweb on ebay. That was before I knew about: http://www.ebay.com/itm/Commodore-128-64k-VDC-Plug-Upgrade-No-Soldering-needed-/380985152237?hash=item58b47c12ed Who I met on www.lemon64.com .

These PCB make it so easy to install the extra RAM, the old method of replacing the RAM chips hardly makes sense. This extra RAM helps some good software work even better. This gives the C-128 a real advantage when it comes to being protuctive. It's an upgrade any C-128 should seriously consider.

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I think I actually have in storage the original 16k x 4 chips I pulled from my C128 20 years ago.

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I think I actually have in storage the original 16k x 4 chips I pulled from my C128 20 years ago.

Does that mean your C-128 has 64Kb of video RAM?

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Received it today, but something's not right :(
post-3056-0-74245100-1440547642_thumb.jpg

Removed it and the scrambled letters went away. For fun I played a round of my Space Invaders port, Alien Invaders (if anybody's interested, the game's available in reply #5)
post-3056-0-38550400-1440547671_thumb.jpg

post-3056-0-94619200-1440547677_thumb.jpg


Jiffy DOS installed fine, really made my uIEC/SD nice and speedy! Tested that out in both 128 and 64 modes.

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Received it today, but something's not right :(

Removed it and the scrambled letters went away. For fun I played a round of my Space Invaders port, Alien Invaders (if anybody's interested, the game's available in reply #5)

Jiffy DOS installed fine, really made my uIEC/SD nice and speedy! Tested that out in both 128 and 64 modes.

 

What board did you get? I haven't that problem before.

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SpiceWare wrote:

 

> For fun I played a round of my Space Invaders port, Alien Invaders...

 

Thanks for that! I'll show it at our next FCUG meeting in September.

 

Celebrating the 30th anniversary of the C128,

Robert Bernardo

Fresno Commodore User Group

http://www.dickestel.com/fcug.htm

 

Cool! One thing that may not be obvious is while you're playing it you can use the + and - keys to adjust the speed of the game.

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What board did you get? I haven't that problem before.

 

 

The one you linked to. I've already contacted them. Going to try a couple things tonight, but if it doesn't resolve the problem I'll return it for a refund as they're sold out so can't do an exchange.

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The one you linked to. I've already contacted them. Going to try a couple things tonight, but if it doesn't resolve the problem I'll return it for a refund as they're sold out so can't do an exchange.

aaascrapdogsunlimited are good to deal with, so you will not have any problems there. I don't know what the problem could be though - never seen that one before. Problems with this upgrade are extremely rare.

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SpiceWare wrote:

 

> One thing that may not be obvious is while you're playing [Alien Invaders] you can use the + and - keys to adjust the speed of the game.

 

Oh, thanks for the hint. I'll try it with the SuperCPU 128, too, and see if there is any speed-up.

It's rare to have a graphical game in C128 80-column mode, and yours is one of the few.

 

Truly,

Robert Bernardo

Fresno Commodore User Group

http://www.dickestel.com/fcug.htm

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It's rare to have a graphical game in C128 80-column mode, and yours is one of the few.

To bad I never finished my 80 column asteroids game. I stopped working on that when I got sidetracked with my new Amiga 2000HD.

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No, it's long gone. At some point after getting the Amiga I was tight on cash and sold my 128, two 1571s and one 1581. I including all the 5 1/4" floppies as they wouldn't work for the Amiga, the 3 1/2" were reformatted for the Amiga. The cash was used for either tuition, rent, or food, don't recall. In the past few years I've replaced everything except the 1581.

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I wrote:

 

> I'll show [Alien Invaders] at our next FCUG meeting in September.

 

SpiceWare wrote:

 

> One thing that may not be obvious is while you're playing it you can use the + and - keys to adjust the speed of the game.

 

The FCUG members were very surprised and pleased with the game. Most of them had never seen a graphical game running in the C128's 80-column mode. The gameplay was smooth and fast, though using the minus key only slowed it down just a tiny bit and using the plus key didn't seem to make a difference (though I may not have noticed if there was a slight speed-up). We liked how the invaders moved even faster as they got to the bottom of the screen. Very challenging! Of course, we liked the nice sound effects. We didn't try it with the SuperCPU 128... perhaps at another meeting.

It ran fine from the uIEC SD. However, when we tried to transfer the program file to a floppy disk for another club member and then when we tried to run it... fail! The game would crash. We'll have to try another way to transfer it to floppy disk.

 

Truly,

Robert Bernardo

Fresno Commodore User Group

http://www.dickestel.com/fcug.htm

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