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Motherboard with NEC V40

Much easier to get an 8088 XT clone and substitute a V20 CPU for the 8088. The V40 uses the same core, just adds on-chip peripherals. And you get the benefit with an XT clone of strict PC compatibility, unlike your board.
 
Chuck(G) said:
Much easier to get an 8088 XT clone and substitute a V20 CPU for the 8088.
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I don't think so... I find this your plan rather hard for me. I've fogotten when I've seen 8088 XT clone last time. :roll:
May be on ebay... but I see no reason for this.
I've tested such an idea not so long ago and ask my friends about 8088 motherboard - they are laughing... :D
I'll try to power this motherboard - if it will be successfull - it will be splendid... if not - so not... :wink:

iLavr said:
The second IC60 EPROM seems to be a characters generator.
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I've tested it with FontEd - it's really a characters generator:

NEC_FONT.gif
 
iLavr said:
I don't think so... I find this your plan rather hard for me. I've fogotten when I've seen 8088 XT clone last time. :roll:
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Really? 8088 PCs are frequently offered here. Right now, in the Marketplace sections, there's a complete Peanut setup being offered.

Of course, I don't know your location--it could be Ouagadougou, in which case I could understand your frustration at not being able to find a system that uses an 8088 or 8086. Even so, I think Andrew Lynch still offers an 8088 kit...

At any rate, have fun! ;)
 
I'm signing on to this thread late. Before you were able to determine the manufacturer, I was going to suggest that the mobo is in reality an sbc. It has a v40 - just like my Ampro Little Board/PC, or whatever the exact designation was. It also has Vadem chips, just like my Ampro. But alas it's just a funky french desktop puter. Looks nice, wish I had one.
 
tipc said:
... I was going to suggest that the mobo is in reality an sbc. It has a v40 - just like my Ampro Little Board/PC, or whatever the exact designation was. It also has Vadem chips, just like my Ampro.
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Have u your Ampro electrical schematic diagram?
Exactly these Vadem chips confused me a lot...
And I can't find yet what's this:

L1A2099.jpg
 
It's the CGA/MGA support circuitry for the 6845. You'll see the same chip in the Commodore PC-1 and on the Paradise Mono/CGA card (PVC2). Basically, you take a 6845, a PVC2 chip, a character generator ROM and a small handful of SSI TTL and you have a graphics adapter.
 
Normerel EEPROM

Normerel EEPROM

I continue to search for information about this "Normerel ST-2" computer...
I've found that may be "Normerel ST-2" stands by "Normerel S Turbo 2". (S = Systemes ? :) )

"Normerel Systemes" seems to be a very strange vendor... :(
There is almost very few information about it in Web.

So I look through ROMBIOS and find also two other character tables there:

NEC_FONT1.gif


Here are Normerel ST-2 EEPROM, if smb want to examine them...
 

Attachments

  • Normerel_ST_2_EEPROM.zip
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Almost all BIOSes have a character ROM table for generating characters with CGA when the card is in graphics mode. So nothing unusual--the characters are most often generated inside an 8x8 pixel box, so they look a little crude.
 
I have a technical manual for my Ampro, probably a partial at this late a date, but it's not going to say much about the Vadem chips that you couldn't figure out on your own. It's a bunch of glue jammed into one package largely. And possibly some typical 8 bit support chips (8253, 8255, etc.). Haven't looked at my A* in a while. I'll try to dig out some info when I can. If you don't hear from me, feel totally free to remind/bug me via pm or rampaging+green+hulk@yahoo.com (remove "+" signs). There's not a lot more I'll be able to tell you about the Vadem chips though. They were likely just some fab house that provided custom logic for sbc manufacturers. You could try contacting Ampro, they're still around I think.
 
tipc said:
I would hope and suspect that w/a Paradise chip/set, it would be a largely compatible machine. Don't be put off by the v40 or other bizarre looking glue.
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Do you figure that the DMA is compatible for the floppy drives? Or the memory refresh? How about the serial port? It's closer than an 80188, but still isn't quite an 8088 box.
 
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Chuck(G) said:
It's the CGA/MGA support circuitry for the 6845. You'll see the same chip in the Commodore PC-1 and on the Paradise Mono/CGA card (PVC2). Basically, you take a 6845, a PVC2 chip, a character generator ROM and a small handful of SSI TTL and you have a graphics adapter.
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Can u give me an advice where can I have a look on Commodore PC-1, the Paradise Mono/CGA card (PVC2) or may be Zenith easy PC schematics?
I do my best googling, but invain... :(
May be I can find this circuits somewhere in this forum but I don't know? I've tried "search" - nothing...

I think a good electrical schematic diagram will reduce the number of my questions...
 
Chuck(G) said:
It's the CGA/MGA support circuitry for the 6845. You'll see the same chip in the Commodore PC-1 and on the Paradise Mono/CGA card (PVC2). .
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I suppose Paradise Video Chip 2 (PVC2) in the Paradise Mono/CGA card plays the same role,
as an Amstrad Videogate Array (20RA043) in the Amstrad CPC64[/b] schematis?

Amstrad_cpc_464.jpg


Isn't it?
 
Chuck(G) said:
Do you figure that the DMA is compatible for the floppy drives? Or the memory refresh? How about the serial port? It's closer than an 80188, but still isn't quite an 8088 box.
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The point is it could be despite the use of the 80188/v40. The designer's could have chosen to not use the onboard peripherals. Perhaps I should have taken a closer look, but since it _is_ using chips made by the same house that supplied for the Ampro LB/PC, it could be just as compatible, which is very. That's my understanding anyway. I haven't exhaustively tested it. But why the use of specialized glue, so much that is, if it's using the onboard peripherals? I was just stating that if they were looking for a high degree of cga/mda/ega? compatibility, likely the rest of the h/w is pretty much there.

I have my technical manual kicking around, perhaps w/i arm's reach these days, seeing I've been going through nearly everything I own w/a fine tooth comb. I'll try *scanning* it, as much as I have, for the public good. It's reasonably thick, so likely it goes into some detail on the Vadem chips, there specific function, etc.

Did you ever look at a Tandy 2000 mobo Chuck? It has ALL of the peripherals found on a 5150. One has to wonder why they used an 80186, but I think it had more to do w/marketing or what have you then owing to improved performance. The Mindset also used it, Televideo Personal Mini (may mine rest in peace), Northstar Dimension. It found it's way into some reasonably heavy duty machines back in the day. But it's primary use was for uControllers. Was there an advantage to using an 80186 over a fast 8088/8086 given you might ignore most of the onboard facilities? You'd probably know before I will.
 
Yes, I've looked at the Tandy 2000 and it fails miserably in low-level compatibility. Believe me, I've been there.

We were sold the 80186 by the Intel guys as being the "next thing before an 80286", so we designed it onto our board (along with the 286). Even though most of the customers eventually ran Xenix, the "sort of" compatibility with the PC (i.e. we could run MS-DOS, but not the low level utilities or games) showed us what a mistake we made. I suspect that Tandy was sold the same bill of goods.

You can probably get very close--heck, I have a V40 box here. But the point is if you're going to throw out the integrated peripherals (even though they're closer to the standard 82xx ones than the ones on the 8018x), why not just use a V20 or V30? The V40 would, in that case, offer no advantage, as the V40/50 is no faster than the V20/30.
 
Chuck(G) said:
Yes, I've looked at the Tandy 2000 and it fails miserably in low-level compatibility. Believe me, I've been there.
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This is a secret? I wasn't suggesting the T2K was h/w compatible, but the reasons for that probably has far more to do w/litigation and very little to do w/the presence of what was necessary to make it compatible. The biggest problem w/regards to compatibility was the usage of totally different graphic chips, which was the case on virtually all other semi or pseudo compatibles. The 2000 was absolutely a pseudo compatible, but was probably the most compatible at the BIOS/DOS function level.

"We were sold the 80186 by the Intel guys as being the "next thing before an 80286", so we designed it onto our board (along with the 286). Even though most of the customers eventually ran Xenix, the "sort of" compatibility with the PC (i.e. we could run MS-DOS, but not the low level utilities or games) showed us what a mistake we made. I suspect that Tandy was sold the same bill of goods."

Precisely. Many vendors were _sold_ on the virtues of the 80186 as a big box cpu. Funny though that it found it's way into gujillions of sbc's. It was all about marketing hype. There was even a mention of it being used in the Peanut. Now it was one of the most successful chips of all time, I think most would agree. But it was pushed into machines oftentimes for no discernible reason.

"You can probably get very close--heck, I have a V40 box here. But the point is if you're going to throw out the integrated peripherals (even though they're closer to the standard 82xx ones than the ones on the 8018x), why not just use a V20 or V30? The V40 would, in that case, offer no advantage, as the V40/50 is no faster than the V20/30."

The point is you _can_ get very close. Some vendors labored to do this. Why we can only ask.
 
iLavr said:
Now I'm thinking about soldering the power connector to it and may be NEC V40 is still alive? :wink:
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If I'll found him alive, I'll try to make something like this:

attachment.php


But I'll try to use my mobo as devboard...

The only inconvenient thing - it's hard enough to do anything without any schematic diagram of any mobo analog... :(
 
tipc said:
The point is you _can_ get very close. Some vendors labored to do this. Why we can only ask.
Click to expand...

It was funny--we had successfully produced and marketed a multi-user 8085 box, with the understanding that we'd move to 16 bits when a good alternative was available. There were 16-bit products available as early as 1975, but they either were low performance (e.g. GI CP1600) and offered no additional bang for the hardware buck or very expensive with very limited production (e.g. Fairchild 9440).

We'd looked at the 8086 and discarded it as not sufficiently advanced. I'd taken some 8085 benchmarks to the local sales office and attempted to run them through their automatic translation software on the MDS and succeeded only in getting a couple of free lunches because the translator gagged. So if we were going to do something new, we came to the conclusion that we'd start fresh.

The engineering staff really liked the Motorola 68000 (we also liked the NSC 32016, but it was still vaporware) and we built up a couple of prototype PCBs and started playing with them. Well, Bill Davidow was on our board of directors and when he heard that we were thinking about using Moto's CPU, he hit the ceiling. We explained that the 8086 wasn't good enough and that the 432 project, if it ever went anywhere was going to be far too expensive. So what could he offer? He got us in with the 80186 and 80286 projects which had silicon, but with lots of issues. Although the company made it to 1985 before declaring bankruptcy, I left in 1981 after it became clear what was going to happen.

The bottom line was that Intel messed up badly. The 8086 was intended to be a stopgap product until Intel could ship the 432 family. When the 432 started foundering, they tried to sell their customers on the 80186 until the 80286 was ready. Intel messed up badly and if it wasn't for IBM, they could have had some hard times ahead. I've always wondered if Intel gave IBM a sweetheart deal on their peripheral chips. After all, they were all 8-bit 8085-family silicon--and that market wasn't a growth market.
 
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