ECS Program Expander was planned... in brown!

[+Lathe26]

While we know that Mattel advertised the never-released Program Expander for the ECS, I never knew they also advertised the brown PAL version.

 

Here's the brown version. Only a low-res image is available.

 

Here are better photos of the white Program Expander, just for reference

 

[Utopia]

Nice find!

[Bamse]

Are they the same aside from the colour?

[Intymike]

Not a photo, but it was mentioned in the 1983 German poster catalog.

 

 

 

Edited March 7, 2019 by Intymike

[intvnut]

Are they the same aside from the colour?

 

Yes, I imagine they're both painted blocks of wood, just painted different colors.

 

(Seriously, many of the prototypes shown were just painted wood. Search for "wood" on that page.)

 

In terms of specs, I can't think of why the program expander would be different between the two other than the color/styling. The expander was slated to include an enhanced BASIC and additional RAM.

Edited March 7, 2019 by intvnut

[mr_me]

That's 8K rom and 16kB ram, would all those chips fit on that skinny expansion card.

 

The white ecs and brown ecs should be the same on the inside, although some might be missing the expansion slot.

 

Does the ecs case have a removable panel to access the expansion slot?

Edited March 7, 2019 by mr_me

[Bamse]

 

Yes, I imagine they're both painted blocks of wood, just painted different colors.

.

???

[Bamse]

That's 8K rom and 16kB ram, would all those chips fit on that skinny expansion card.

 

The white ecs and brown ecs should be the same on the inside, although some might be missing the expansion slot.

 

Does the ecs case have a removable panel to access the expansion slot?

I didn't know the ecs had an expansion slot

[Intymike]

There it is:

 

 

[Intymike]

At the brown one as well:

 

 

[Bamse]

Oh yes

[+Lathe26]

There was a planned expansion connector, but only some ECSs have it installed. As far as I can tell, the connector is only populated on some white ECSs and I've never seen / heard of the connector existing on a brown ECS. On all ECSs I've ever seen, including a late-model prototype / internal testing ECS I got on Monday, the plastic cover is always glued.

 

Here are some photos of the glue on a white and brown ECS.

 

 

[+Lathe26]

As for the connector itself, here are 2 ECSs, one with the expansion connector and another without it. These are not the best photos. Informally, I get the impression that more ECSs are missing the connector versus those that have it, but I have no hard data to back that up.

 

Side node: normally the medium-sized daughter board is not vertical like that. The plastic screws had been removed so the daughterboard was moved out of the way to see the 2KB SRAM chip underneath.

 

 

[intvnut]

As for the connector itself, here are 2 ECSs, one with the expansion connector and another without it. These are not the best photos. Informally, I get the impression that more ECSs are missing the connector versus those that have it, but I have no hard data to back that up.

 

Side node: normally the medium-sized daughter board is not vertical like that. The plastic screws had been removed so the daughterboard was moved out of the way to see the 2KB SRAM chip underneath.

 

2019-03-07 12.36.56.jpg

 

2019-03-07 12.37.41.jpg

 

What's the date code on the AY-3-891x on the first one above? I can read the second one (8306).

 

The first one looks like 8808, to which I say:

 

 

Now, if it says 8308, then that's a bit weird, but perhaps explainable if both were produced noticeably later in 1983. That seems likely, in fact, given that neither has 4182 tagged on it, but rather 0098, similar to other GI ICs used in the Intellivision II.

[CatPix]

Ah, so that's why there is that trapdoor... Interesting!

 

I have a brown ECS and on mine, the connector is missing, but the cover wasn't glued.

Maybe very early brown models didn't got glued? I mean, it takes a real effort to open it, it's tightly fitted and can't reallly pop out by mistake.

Of course it could have been carefully opened and "deglued" by a previous owner, but that would be a strange thing to do; especially to care about removing all traces of glue even on the inside of the shell!

Unless the glue easily come off after a few year, but then... where are the remains of it?

 

If that helps, my ECS S/N is P3 00980.

 

 

That's 8K rom and 16kB ram, would all those chips fit on that skinny expansion card.

 

Easily... the slot is going real deep in the expansio module, almost to the bottom, that leave a lot of surface for an expansion board.

 

 

 

Those are 16 Ko ROM chips for the ZX 81 and Spectrum, so they are from 1981/82.

A 8KO ROM wouldn't be much bigger than a CPU of the era in a worst case situation, so, that would very really fit into an additionnal card of the time. It could even probably accomodate 64 KO of RAM as well.

Edited March 8, 2019 by CatPix

[intvnut]

Ah, so that's why there is that trapdoor... Interesting!

 

I have a brown ECS and on mine, the connector is missing, but the cover wasn't glued.

Maybe very early brown models didn't got glued? I mean, it takes a real effort to open it, it's tightly fitted and can't reallly pop out by mistake.

Of course it could have been carefully opened and "deglued" by a previous owner, but that would be a strange thing to do; especially to care about removing all traces of glue even on the inside of the shell!

Unless the glue easily come off after a few year, but then... where are the remains of it?

 

If that helps, my ECS S/N is P3 00980.

 

 

 

Easily... the slot is going real deep in the expansio module, almost to the bottom, that leave a lot of surface for an expansion board.

 

 

 

Those are 16 Ko ROM chips for the ZX 81 and Spectrum, so they are from 1981/82.

A 8KO ROM wouldn't be much bigger than a CPU of the era in a worst case situation, so, that would very really fit into an additionnal card of the time. It could even probably accomodate 64 KO of RAM as well.

 

 

In 1983, the 8K ROMs would fit in a 24-pin DIP. The ECS itself has 12K of ROM in a single 24-pin DIP. Alternately, they could use a 40-pin DIP with a ROM variant that latches address lines for static RAM.

 

For the RAM, they have a couple options:

• Some combination of SRAMs such as the 6264. Static RAMs in this category are in the 24-pin to 28-pin range. Easily fits in that space.
• Dynamic RAMs such as the 4116s you showed. Those are more complicated as they need a refresh circuit and some arbitration logic. The PlayCable and Keyboard Component both had that, but it would likely need a custom circuit, or something like the MC6883 SAM.

 

You could easily build this expansion from 1 40-pin DIP (GI ROM with address latch) and 2 28-pin DIPs. As long as the 40-pin DIP output appropriate chip selects, you wouldn't need any other support hardware. Or, maybe you need one small TTL chip to generate 2 chip selects from the one chip select if the DIP doesn't do it for you.

 

I believe the RO-3-9506 fits the description. I can't find a data-sheet for it, but the description in MAME indicates it's an 8K-decle ROM w/ external address decoder. So far, though, we've only seen it used as a 4K + 256 word ROM in the Intellivision 2. In any case, the imagined ROM chip should be similar to the RO-3-9502, just with higher capacity.

[+Lathe26]

 

What's the date code on the AY-3-891x on the first one above? I can read the second one (8306).

 

The first one looks like 8808, to which I say:

 

I-dont-believe-you.gif

 

Now, if it says 8308, then that's a bit weird, but perhaps explainable if both were produced noticeably later in 1983. That seems likely, in fact, given that neither has 4182 tagged on it, but rather 0098, similar to other GI ICs used in the Intellivision II.

 

I looked at the date codes and they say:

 

But seriously, the date code for the top ECS's PSG one is 8308 (and the bottom one is 8306). I also have a 3rd ECS with PSG date code 8308 and a proto ECS with 8306. That said, all 4 ECSs have ROM chips with later date codes ranging from 8329 to 8335.

 

As for the brown ECS, it's possible that the glue was removed but then again it might have been manufactured that way. I have not tried removing the glue so it might brittle and easy to move (or not). There's a photo I saw online that I can't find at the moment where someone removed the glue and it looked like it came off in one chunk.

 

Serial numbers are tricky with ECSs. Each ECS has 2 different serial numbers:

• One on a sticker outside on the plastic
• One on a sticker inside on the circuit board

From looking at the 4 ECSs I have, the outside serial numbers don't help determine whether the expansion connector is present or not. I have high serial numbers with the expansion connector and lower serial numbers that don't have it. Interestingly, it looks like the white ECSs have 6 digit serial numbers while brown ECSs have 5 digit serial numbers (not counting the pre-printed "P3" part).

 

However, the internal serial numbers appear to have a pattern, though this is from a tiny sample size of only 4 ECSs that could easily be disproven later:

• L00071294 - no connector
• L00048046 - no connector
• L00003306 - has connector
• 00018 - has connector (this serial number might not count since it is hand-written in the proto ECS)

Going back to the Program Expander, I wonder what it's stats were actually going to be. In the 1983 catalog, it was listed as 8K ROM and 16K RAM. However, the old IntellivisionLives.com site listed it as 12K ROM and 16K RAM.

 

1983 Catalog:

 

IntellivisionLives.com

https://web.archive.org/web/20161111164600/www.intellivisionlives.com/bluesky/hardware/ecs_tech.html

[Utopia]

Well there is a new can of worms!

 

Mine are both Australian PAL brown versions (currently in storage) but I wonder what they will reveal?

[intvnut]

However, the internal serial numbers appear to have a pattern, though this is from a tiny sample size of only 4 ECSs that could easily be disproven later:

• L00071294 - no connector
• L00048046 - no connector
• L00003306 - has connector
• 00018 - has connector (this serial number might not count since it is hand-written in the proto ECS)

 

 

Add L00052302 with connector.

 

The U52 has date code 8334, and says REV H.

 

I have several more ECS units buried in storage. That'd double our data points at a minimum. Oh, and the door on this one was glued.

 

Now, I could swear I've come across a grey ECS unit whose expansion door wasn't glued, but without pics or the ECS itself, I can't prove it.

 

 

Going back to the Program Expander, I wonder what it's stats were actually going to be. In the 1983 catalog, it was listed as 8K ROM and 16K RAM. However, the old IntellivisionLives.com site listed it as 12K ROM and 16K RAM.

 

If I had to guess, the specs were in flux. I do know that the built in ECS EXEC explicitly does the following:

• Scans $7xxx for paged ROMs starting at PAGE $F and working downward. This allows up to 16 ROMs to be put there, with the highest page number winning.
• Flips in $Cxxx PAGE 1 to look for BASIC extensions.

Over at PapaIntellivision, CCF10232011_00026.pdf mentions "PAGE 7" was reserved for Extended BASIC, but doesn't say what address range. So, at best we can surmise it's at least 4K, probably at least 8K, and maybe bloating toward 12K by the time it was canceled. I didn't see much else about the program expander at PapaIntellivision.

 

Now here's a different detail: That same PDF mentions that $Cxxx was reserved for IMI expansion, and indeed the "v3.3", "v4.1" IMI carts have ROM at $Cxxx. Here's the killer question: Is the $Cxxx ROM paged?

 

I suspect the answer to that last question is no, as I did try running these with the ECS enabled, and the ECS EXEC did try switching in $Cxxx PAGE 1. Since the IMI code is also at $Cxxx, this would have either flipped-away the IMI code (if it was paged), or caused a ROM conflict (if it wasn't). Either way, the IMI code would not run as intended I'd guess.

[Intymike]

Now I have to open my ECS's.

Edited March 8, 2019 by Intymike

[Intymike]

Brown ECS with Connector and glued trap door.

 

Outside number P3 00115

 

AY says 83 06

 

Is the 00509 the internal number? I didn't find another one inside.

 

 

[Intymike]

btw. the oldest chip that I found on the board was 83 01, the newest was 83 24.

[Intymike]

My 2nd brown ECS. No connector, glued trap door.

 

Outside no. P301653

 

Inside no. L00075216

In this one I found the number as you described it. The other one has not such a number.

 

Chips range from 83 08 (AY) until 83 35 (U52)

 

btw. at testing after reassembling I discovered that Scooby Doos Maze Chase has 6 voice music.

Edited March 8, 2019 by Intymike

[Intymike]

My first grey ECS with the lowest serial no. has no connector and glued trap door.

 

Outside no. P3054687

 

Inside no. L00025224 2

 

Chips range from 83 06 (AY) to 83 32 (U52)

 

Aside from being very dusty, the volume knob was not to remove so I couldn't remove the upper shield.

Edited March 8, 2019 by Intymike

[Intymike]

From dirty to shiny. My best looking ECS so far.

And when you think there are no surprises anymore you get a grey ECS with connector and glued trap door.

 

Outside no. is P3071341

 

Inside no. 4 L00001976

 

Chips from 83 07 (AY) until 83 33 (U52)

Edited March 8, 2019 by Intymike