WOW! Look what I found in a junk 800 - 3Bit Full-View 80 and ?

[KLund1]

Got a crappy 800 for parts. I opened it up and looks what I found!! Almost gold!

80 card, 16K mod, and an Intac 32K card!!

 

The 3Bit cables need a bit of cleaning, but overall it looks like it is good condition.

 

But the ram card has me stumped!! The wire out the top goes to a toggle switch on top of the case. This looks like a pro job mod.

The label reads Copyright 1983, S.C.S.D. Inc

On the back of this card there is a hand written white sticker that reads: Jump Back Board for Intec 32k Mod (use 2nd slot). It is the same hand as the copywrite.

 

Then there was the order of how the cards were installed. Back to front:

3Bit

16Ram

32K ram

empty (no 10k Rom card!!!)

 

I have not powered the machine up. It is in not that good of condition. Smells like smoke, and the speaker is rattling around inside.

 

Any thoughts about the ram card mod, and why no OS card?

[1050]

My guess would be that somebody needed the ROM card

so they took it.

 

Layout you report is NOT right by the Bit 3 diagram.

I'm thinking the directions on the 'jump back board'

are too open to improper interpretations?

 

S.C.S.D. appears to have owned CSS at one time.

Probably before Bob Puff took over CSS at least that

is what I can gather from an ad for the "Pill" in

a Compute magazine that google hit on. page 60

http://nleaudio.com/css/

 

Oh look an ad for a new 1050 - only $349!

16K board for the low, low price of $89...

http://www.commodore.ca/gallery/magazines/compute/Compute-043-04.pdf

 

Back in those days I couldn't even afford a baloney

sandwich for lunch let alone an issue of Compute.

 

Would be nice to know the numbers off those ram chips

on the 16K S.C.S.D. board, can't read from the picture.

Have my suspicions that the 16K board might be axlon

type ramdisk and the switch on those typically turned

the extended memory off. Never understood really why,

unless they just did that because they could.

 

You should maybe buy a lottery ticket?

I thought I was lucky when I found a Happy in a

$25 goodwill 1050.

[KLund1]

The ram IC's in the 16K card are MM5290n 16K chips. the three on the far right are covered in epoxy.

[1050]

Thanks, couldn't see the far right one at all due to

sticker on it. So normal size ram chip means it's not

an axlon but we have 3 bits used and it's on a Bit 3

machine - hmmm.

 

S.C.S.D. has perhaps figured out how to turn Bit 3 on

or off with the switch? But only with this 16K ram

board with it's epoxy protection. Just guessing of

course. A good deal before my time too, a lot of

older stuff has left no paper trail on the interwebs.

[KLund1]

Here are the front and back of the switched 16K card.

Looks like the switch turns on/off the ram. Possibly used for a hidden ramdisk? Turn on/off extra video ram? Hide the ram from the rest of the system for some reason. Or maybe a way to switch from 40 column ram memory display to 80 column Ram?

[Mathy]

Hello KLund1

 

Could it be a switch to switch in the 4 kB RAM the 800 is missing? Turning it from a 48kB computer into a 52kB computer? IIRC CSS did something similar for "The Impossible" upgrade. Since CSS was related to SCSD...

 

Sincerely

 

Mathy

Edited May 5, 2018 by Mathy

[gozar]

Could the switch set the ram to read only to defeat the copy protection of dumped carts?

 

 

Sent from my iPhone using Tapatalk

[1050]

There is only 16K here so no ramdisk is possible, this

was the line of my first inquiry. I was shot down,

did you not see the blood?

 

Only other suggestion I've got is that S.C.S.D somehow

figured how to package a 40 column machine along with

the 80 column machine by turning off the Bit 3 device

or at the very least misdirecting it back into a 40

column display. If Bit 3 needed extra memory, wouldn't

they have included it on their very expensive board

already instead of rely on someone else to hack their

work?

 

I see a cut off red wire coming out of the grey epoxy

module that CSS made famous as un-hackable stuff in

there. I see jumpers on the back that often are used

to address strange and new locations probably unique

to Bit 3 alone. Two the 16K ram chips have been covered

up by convenient spillage of more grey epoxy. I suspect

those two to be possibly 64K chips working only for

those two bits that Bit 3 needs at some special address

unique to Bit 3 only.

 

I would worry about 5% about the red wire cut off and

defeating the use of the board. You still have a Bit 3

and it would work with a standard 16K board anyway. Cut

wire could easily be version 2 of the device modded

this way because of extra talent installed on the back

side as to another jumper added there doing the work

of the red wire now cut off. They made these 100 at a

time, it's likely they sold off early versions where the

red wire was routed to the back side and then they

found it was better to just cut it off and obfuscate

the system entirely by use of new addressing jumper.

In other words I'm thinking it would work as soon as

you put the 16K board into the third slot which is

NOT where you found it.

 

They already had 'The Pill' in cartridge form to do

the read only ram aspect of faked cart code, they

would not then sell this version doing the same thing.

 

In my opinion it just toggles the display between 40

and 80 columns. Something that Bit 3 should have done

in the first place but just didn't get around to it?