SE/30 Xceed greyscale adapter cloning thread

[Huxley]

I'm following this thread and have nothing of value to add given my complete lack of electrical engineering / programming skills, but I can definitely say that I'd happily help fund a project along these lines, in whatever format that makes sense (chipping in to help cover development costs, pre-ordering a couple kits, etc.). Having a greyscale SE/30 would be awesome. If there was a "stretch goal" to incorporate Ethernet too, I'd be super excited and willing to pay an additional amount that is probably unreasonable LOL. My current "main" SE/30 has an Ethernet card installed and I'd hate to lose that... but I agree with all the comments above about needing to avoid 'feature creep.' I don't want or need an external monitor, a CPU upgrade would be cool but is almost certainly unrealistic, etc.

Carry on - I'll be cheering from the sidelines!

Huxley

 

[Trash80toHP_Mini]

@pcamen thanks so much for those great pics. As you can see, there's no ASIC on board, it consists of discrete components. Getting one of these cards into the hands of one of out resident boffins for schematic development will be the first hurdle. Translating that into a set of modern components the equations of which are easily tweaked along with a crystal swap(?) will allow the techies to fiddle with it until it speaks A/B and Grayscale Neck Board.

Yes! And accelerated graphics would be great! I would back an SE/30 Xceed greyscale adapter cloning project.  

Not sure QuickDraw acceleration is needed so much on a PDS card at these resolutions. Other than the Pivot Cards, which aren't spec'd, my SuperMac ColorCard SE/30 is the only 030 PDS card listed as accelerated on LEM.

 

[Trash80toHP_Mini]

I haven't been able to upload attachments for several days. I get a: There was a problem processing the uploaded file, -200 error every time, so here's a link to a 306-48 pic on eBay:

It consists of VRAM, EPROM, 74ALS series logic, GALs, Oscillator Cans and a RAMDAC. NO ASIC! []
AM81C471-35JC

edit: links from the 'Bay aren't working either, at least not that one. Gotta click on it.

 

[pcamen]

I think my card is a 306-30.  Anyone know what the difference is between that and the 48?

 

[Trash80toHP_Mini]

Dunno offhand, there's not a lotta info out there. If the pics you posted are of your card, it clearly says 306-48.

Micron seems to have spent ZERO money advertising SE/30 VidCards of any sort. The only ads I found casually mentioned them along with the NuBus Cards, which wasn't much to begin with. They spent their advert money on the IIci Cache Card and JPEG Compression Card. I'd post a pic of the article if I could to put it into perspective. MacUser editorial content regarding Micron's Color30/Gray-Scale 30 Kit amounts to this reportage:

Micron Technology ([800] 642-7661] has also introduced three budget cards: one for NuBus machines and two for the SE/30. The XCEED MacroColor II ($569) is a 24bit card designed for 640-x-480-pixel displays. The XCEED Color 30 ($339) is an SE/30 PDS card that can render 8-bit color or gray scale on 640-x-480-and 640-x-870-pixel displays. The XCEED Gray-Scale 30 ($89) is a video adapter card for the SE/30 that, when it's installed in conjunction with the Color 30, turns the SE/30's internal display into an 8-bit gray-scale display.

MacUser October 1991  55

We think these things are a big deal today, but not a lotta hoopla about them back when it would seem. Gotta pull my MacWorld Archive backup from the NetBook over here to search it. I wonder if anyone made a big deal of it in the day? In April 1992 MacUser made a bit of a thing about external display cards for PowerBooks like Envisio's for my PowerBook 100. But no other mention of Micon's boards for the SE/30 at all from the October 1991 announcement through December 1992 in my search for "xceed."

It's amazing how little these things cost when new. Definitely budget cards as described.

 

[Jinnai]

Wish we could get one for $80 today.

 

[Trash80toHP_Mini]

Best price I found was MacConnection's Feb. 1992 ad: $279 Color30 + $75 Gray-Scale30 = $354 which doesn't seem like a whole lot when compared to 24-bit, QuickDraw accelerated NuBus Cards for 21" Displays.

3-4x that low quote doesn't sound all that outlandish to me now, given the incredible demand. MacConnection's asking price would be $706 today. Dunno what folks think they're looking at in buying a clone, but for sure 50-60 bucks has gotta be a badly lowballed estimate the way I see it.

 

[Jinnai]

While I agree with you, I wouldn't be willing to pay $700 for a clone card with no out of production parts in it.  

 

[jessenator]

Well the $80 was just for the yoke, not the PDS card itself, the way they worded it. Confusing though that they call it out as if it was a completely different PDS card. Probably because the lay user would've taken it in to get in pro installed?

I'm also of the mind that if there's a way to replicate the design without resorting to NOS components, that might be the more economical solution.

Where are we at as far as initial development costs (rough estimate)? Would we need to shell out the $500-$800 (not to mention sacrifice someone's Color30)?

 

[pcamen]

Dunno offhand, there's not a lotta info out there. If the pics you posted are of your card, it clearly says 306-48.

Yea I got mixed up between my card and my greyscale 30 card.

 

[pcamen]

Can anyone clarify whether the analysis of the greyscale card to understand it well enough to reproduce some or all of it will be a destructive one or not? 

 

[EvilCapitalist]

My question, with regards to the card destruction, is there any way of telling ahead of time whether the reverse engineering process would be successful in terms of being able to replicate the card fully after going through it?  I certainly wouldn't want to see a card destroyed unnecessarily if there's no guarantee of success.

 

[Trash80toHP_Mini]

Can anyone clarify whether the analysis of the greyscale card to understand it well enough to reproduce some or all of it will be a destructive one or not? 

That's a good question. Consensus here appears to be that doing an internal grayscale only card is step one., So no rare Color30 card needs to be put at risk. It's not nearly well documented enough for a clone attempt at present. The notion of doing an internal only version of the 306 modified for internal grayscale has been kicking around since April. So a more common, far less valuable 306-48 might meed to be sacrificed, but only if that should become absolutely necessary, at this point that's uncertain.

Replication the Color30 external output is not worth the attempt. Implementing a far better resolution should be the second step IMO.

 

[Bolle]

Modifying a 306-xx as far as I see it would need:

-altering the ROM to tell the correct resolution to the OS/driver - hopefully that will be enough and the driver is smart enough to do the rest

-altering the line and pixel counters in the GALs to values that make sense for the new resolution - this needs some calculation to be done as they seem to count front-/backporch as well to allow for proper blanking

-calculate the pixel clock matching what is implemented in the counters to get the correct refresh rate

The thing with having an output only card that does not sync to the logicboard sync signals can kill the analogboard as there is no protection present for out of range signals.

Standard Micron CRT neckboard can be used wired up to the DB15 output. Signal levels should be ok as the Color30 just dumps the RAMDAC outputs in there as well.

Video ROM probably has to be pulled from the logicboard to get the internal ghost screen to go away.

As far as I know schematics for the 306-xx are not out there. Making them would be non-destructive if I can get one into my hands.

Slightly OT: I just got my Color30 to kind of work with the Turbo 040. The card itself works well with the 040. The only problem it has is that the mode setup of the RAMDAC registers does not seem to work properly.

That way most of the time the card will fail to initialize screen output correctly but once every few resets I could get it to display at least something that would let me see enough to navigate to the monitors CP and change color modes a few times until I get a useful picture on an external screen:

https://imgur.com/a/CxY1nCk

 

[pax]

Slightly OT: I just got my Color30 to kind of work with the Turbo 040. The card itself works well with the 040. The only problem it has is that the mode setup of the RAMDAC registers does not seem to work properly.

That way most of the time the card will fail to initialize screen output correctly but once every few resets I could get it to display at least something that would let me see enough to navigate to the monitors CP and change color modes a few times until I get a useful picture on an external screen:

https://imgur.com/a/CxY1nCk

@Bolle Interesting. I’d love to try the same thing. Did you make any modifications to either of the cards?

 

[Trash80toHP_Mini]

The thing with having an output only card that does not sync to the logicboard sync signals can kill the analogboard as there is no protection present for out of range signals.

Standard Micron CRT neckboard can be used wired up to the DB15 output. Signal levels should be ok as the Color30 just dumps the RAMDAC outputs in there as well.

Video ROM probably has to be pulled from the logicboard to get the internal ghost screen to go away.

The way I read the Color30/Gray-Scale neck board setup doesn't quite jibe with yours. The harness connecting Color30 to the A/B appears to be pulling the dot clock frequency, interrupts, timing of signals with the CPU off the A/B from J2 and supplying those signals to the Color30. Color thirty processes the 8-bit version of the ghost image from there and sends some signals back to A/B J3 while sending the grayscale image to J5 on the Neck boardwhile four signals are supplied to it from A/B J3.

You'd need to have internal Video ROM and Slot E "VidCard" doing their thing to sync production that ghost image in 8-bit with the Color30 feeding those signals in putting together and substituting GS input for the B&W image, but at 8-bit depth on the PDS interface with the CPU. The card then substitutes the grayscale feed to the GS neck board in perfect sync with the ghost image.

Can you tell from the schematics available for the Color30 if there is input from a crystal on board for the GS section? My thinking would be no, it syncs with the the two A/B connections. In that case the 603-48 clone might need no oscillator at all on board?

 

[Trash80toHP_Mini]

Ouch! Couldn't have said that less clearly it would seem.

Lets try that again:

SE/30 Video is interacting with CPU, A/B and MIA standard Neck Board, doing its 1-bit VidCard thing in PseudoSlot $E memory space as always.

Color30 is building exactly the same image in parallel on the PDS in Slot $whatever memory space, but in 8-bit depth.

Color30 is monitoring/shadowing memory activity between built in video system and main memory/CPU as it fills its VRAM buffer with the 8-bit version of the SE/30.

It's a symbiotic relationship between the two video systems until the Color30 cuts the standard neck board feed off at its knees on the A/B, letting what looks like five lines interact with the Grayscale Neck Board while substituting its modulated grayscale feed over what looks like a pair of lines from the Color30 connector to paint the grayscale image on the CRT in perfect sync with what would have been a B&W stream of same.

Not sure which is a ghost or shadow image, but it looks to me like you can't really have one without the other, at least not without possible damage the A/B Bolle has been talking about.

On another note: I see two versions of the Grayscale cards, one with a pair of crystal cans as on the 306-48  .  .  .

.  .  .  and one with apparently none?

View attachment 14077

I wonder which is which and if 1024x768 is easier to couple with the standard video dot clock than is 640x480? Have we got definitive info on what model is 640x480 out and which is 1024x768 out?

Is there a crystal somewhere in the lower picture I haven't found? Maybe in the black box on the lower left corner? If not, this version of the card appears to be working off the SE/30's internal video clocking, etc. that I've put my head on the chopping block about in the jibberish laden WAG above? :blink:

edit: @Cory5412 why are crosslinks working from content posted here, but not links from 'fritter content or elsewhere? Also, why do I keep getting that -200 error every time I try to upload an image. ISTR trag couldn't upload PDFs a day or two ago as well.

Just tried to upload that 139kb wiring harness file I snagged off 'fritter and got the same error.

 

[jeremywork]

Is there a crystal somewhere in the lower picture I haven't found? Maybe in the black box on the lower left corner?

The silkscreen for that black box is marked Y5- quick searching seems to reveal Y is most commonly used to denote a crystal oscillator (and it looks to have the right pin footprint.)

https://electronics.stackexchange.com/questions/16795/silkscreen-labels-for-components-what-could-y-be

 

[Bolle]

The crystal vs. no obvious metal can crystal is just different revisions of the Color30.

The later ones had a video timing generator while earlier ones had the two crystals.

 

[Trash80toHP_Mini]

Interesting, this was what got me thinking about the inter-connections on the harness:

For external vertical sync Maverick will wait for an
external sync pulse at each vertical front porch period. The falling edge of the
active low external sync will force the vertical timing state machine to go into the
internal vertical sync state.

Probably wrong, but sounds to me like the card is using the SE/30 internal video's sync pulse as the primary input for timings?