AMSTRAD PC-20 512K PERSONAL COMPUTER

[00WReX]

I'd never heard of one of these till I came across this...

http://www.ebay.com.au/itm/AMSTRAD-PC-20-512K-PERSONAL-COMPUTER-RARE-ONLY-ONE-WORLD-EBAY-LOOK-/120814113117?pt=AU_comp_dekstop&hash=item1c2115115d

In Australia, so my neck of the woods...but I'm not interested.

Just thought I'd put it up incase somebody here is...

Cheers,
Shane

[steve]

Looks nice, you should buy it and create a page about it for the wiki.

[Lazy Dude]

   looks like a moody looking piece of hardware. To my mind cutting off the power cable like that is a way of saying this machine is broken do not use, hence they state it's for spares only

[AMSDOS]

I've banged on about this machine a bit, probably because it's slick slimline look which is somewhat comparable to a CPC Plus!    I think of this as Amstrad's Answer to the IBM PC Jnr which came out in 1984, only Amstrad released this machine around 1989-90, one of my Australian Personal Computer magazines reviewed it, which is how I originally came across the machine (I had no idea of it's existance). The Review didn't favour this machine either at the time (which was up against Amiga's and Atari's), which is probably why it's Rare nowadays! They did mention however that it's cheap price tag (Au$900) would make it a reasonible machine for routine tasks - there were probably a hundred over machines at the time which would do the same thing!    Probably what did it in was CGA video which by then would have been considered outdated, though CGA is one of those ports which could incorporate all sorts of effects!    Beyond that one would have to know what could be done, if it had specific tricks, features in the video card, etc.

[Ynot.zer0]

reminds me of one of these

[MacDeath]

The sad part with those is that they are CGA and beeper.


get a custom video card with a few extra videos mode so it is compatible with some EGA (like the 320x200x16 mode), but with possibility to choose freely the 16 inks from the 64 colour palette... and a custom sound card with an AY and you get a decent pseudo Atari ST but "IBM compatible"... and fit for gaming.


IBM killed the PC gaming in the 80 with its CGA/EGA and beeper specifications...

Also, you can't add card inside and close the casing, those Card slots should have been oblique.



Anyway it should be fun to see if a modern PC motherboard can be fit into those...

[Gryzor]

Well, it certainly looks sexy, but the one below was ever sexier...

[Bryce]

The EuroPC isn't that rare, they often come up on ebay. The PC20 / P200 (yes they are identical machines in a different coloured housing) were quite rare, but they were pretty shit, there's not a lot you can do with it.

Bryce.

[MacDeath]

A friend of mine had this in the late 80's/early 90's (very early...)



It was CGA and beeper too...

while Odd looking, the dual disk drive was actually awesome...
Yet an XT PC...



Concerning the PC20/PC200 (Amstrad or Sinclair...black or White) it was actually a product from the Sinclair Research "vault"...
Dating from the time Amstrad bought sinclair.

Amstrad released it a bit Late I guess.

The casing is really cool looking... well, like a good looking Atari ST or Amiga500...

Sadly, they improved nothing, the Amstrad version just lacks the TV port plug...


The sad part with CGA : while done to be plugged on TV-like monitor, it wasn't powerfull...
But EGA needed a special monitor, uncompatible with TV standards because of the 640x650x16/64 mode...

And all the CGA-compatible modes couldn't properly re-set inks...

That's why a good PC at the time simply couldn't get the connect on your TV formula the Atari ST or Amiga or whatever Home computers had at the time...

Amstrad quite missed the point to impose a real upgraded CGA standard...


Remember when PC1512 was released...
IBM bitched it because it wasn't "fully CGA compatible"... while it was actually better (640x200x16 mode...)

Also we remember the "where is the cooler fan?" infamous counter-argument...

Fact is, CGA was complicated for nothing...
To change the "inks" you actually ... can't... the only fully changeable colour is always Black only.
.. WTF ?
So you had a not that bad 16 colour palette but actually could only have 2 pre-set 4 inks palettes from that.


Same kind of problem was then passed on EGA with it's fixed 16 colour palette (the CGA extended palette) in 320x200x16... and most of the cool colours from the 64 colour palette were never used nor usable actually (in most normal games...).


There, a good pair of links that explain well the CGA and EGA...

http://members.chello.at/theodor.lauppert/computer/cga.htm
http://members.chello.at/theodor.lauppert/games/ega.htm

On the paper, EGA is actually excellent, in reality the fact most of its video modes were "CGA legacy" logic killed it.
Also the fact you simply couldn't conect it on a TV...


Even the CPC managed to do what the CGA should have been...betterly.

The PC20 / P200 (yes they are identical machines in a different coloured housing) were quite rare, but they were pretty shit, there's not a lot you can do with it.

Well, you can play good old CGA games...
Like Populous or Monkey Island, Indiana Jones3 adventure game and so on...

There is an internal extension port, I guess you may connect a better video card on this, perhaps even a VGA... or not.
But the drawback was that then you couldn't shut the casing.
Perhaps if this extension port was oblique or horizontal...  the diagonnal may be large enough to get this thing closed with a card inside.

[AMSDOS]

Agreed CGA was out of date at the time and even though there was EGA, to me that Video Card just couldn't hack it, it simply wasn't backward compatable to a CGA, IBMs were funny beasts because CGA had Low-Res 160x100 graphics in 16 Colours, though to allow it to happen on an IBM or Compatable, you need to write the whole print routine, and perform some other stuff!    I think IBMs PC Jnr actually supported this though that machine came out in 1983 or 4, you could get away with CGA back then, though late 80s early 90s, it could have been so much more impressive and competative with them Amiga's and Atari's. VGAs kind of fix what EGAs didn't address and allow better support for CGA modes, again Low Resolution wasn't standard, though with a bit of mucking about it was there, even better when you revert to the 8x8 character set which is standard on CGA! 

Don't be fooled by a simple PC Beeper (Speaker), depending on computer - some don't have a volume, though some do, and I've heard some interesting sounds, tunes & effects done with a PC Speaker, unfortunately I don't have any examples on hand!    Though I suppose you'll just have to look out for things like Games, I even found a program simular to some of our Amstrad Type-ins which captures Digital Sounds and plays them back on a PC Speaker!

[Bryce]

This time I have to admit, that the weaknesses of CGA/EGA are a hardware problem. It was decided that the interface signals, ie: the connection to the monitor should be purely digital. So you end up with RGB where each colour can only have two on-states (normal / bright) and off (ie: black). This is what made CGA such a terrible format.

Bryce. 

[MaV]

The Euro PCs, while they look very nice and clean, have one grave problem. Their RTC-batteries are soldered directly onto the board, and not at a corner but in the middle. Since after ~20 years those are 100% likely to have spilled their acidic content onto the board, most of them are a mess inside.
I have two of them which I hopefully will be able to revive - chances are slim however.

@bryce: Funny, back then I thought digital connections were the "right" thing to do. I had to warp my brain around the fact that VGA's were analog connections (it's a computer for god's sake! )

CGA and even EGA were both a mistake, the former because of it's paltry palette the latter because of it's screen ratio.
In VGA 640x480 you draw a circle without having to correct the y-coord like in 640x350. And the 320x200 VGA mode had byte-size pixels, so programming was easy. One pixel left or right -> subtract/add 1 from the current position; one pixel up/down -> subtract/add the length of the screen in pixels (ie. 320) from the current position; + no business with masking pixels for colour, good scrolling, and a whopping 262144 colours to choose from.

[MacDeath]

Don't be fooled by a simple PC Beeper (Speaker), depending on computer - some don't have a volume, though some do, and I've heard some interesting sounds, tunes & effects done with a PC Speaker, unfortunately I don't have any examples on hand!

Loriciel's game : Disc...
The intro while in CGA only had a sweet chiptune, similar as on Atari ST.


Also : Crime Wave, was in full "real sound".

But on most PC, the beeper was simply horrible and you couldn't even turn the volume down !


Anyway the funny part is that in 1990... CGA was still fully supported by most games...
The turning point was perhaps around 1992.

[Bryce]

@MaV: Colours (and our eyes) are analogue, so having an analogue scale for RG and B was much better As we found out with VGA, it was just strange that after all the 8/16bitters had good colour displays, that the PC didn't go straight from Hercules to VGA.

Luckily the EuroPC used a standard 3.6V battery for the RTC, and these are still easy to get. If you send me the EuroPC boards, I can replace the batteries for you.

Bryce.

[MaV]

Luckily the EuroPC used a standard 3.6V battery for the RTC, and these are still easy to get. If you send me the EuroPC boards, I can replace the batteries for you.

Thanks, bryce. But the problem is the board itself, not the battery. One doesn't react when I switch it on, although the main chips receive the 5v. The other board's bios sends a code indicating that one of the chips has a problem.

We better continue with a PM, if you would like to help me.

[Gryzor]

@Bryce: did I say the EuroPCs are rare? Two of my friends had one, poor lads...
@MaV: soldered batteries? What the....

[Bryce]

Most of the older machines with RTC or battery backed RAM used those 3.6V soldered in batteries (exactly the same one that was used on the Inicron RAMROMBox too). When they leak they destroy quite a bit. I'm currently trying to save an Amiga 500 which has badly suffered from the same fate

Bryce.

[Gryzor]

Yeah, I know, but I would have expected the practice to have died with the advent of PCs...

[TFM]

Most of the older machines with RTC or battery backed RAM used those 3.6V soldered in batteries (exactly the same one that was used on the Inicron RAMROMBox too). When they leak they destroy quite a bit. I'm currently trying to save an Amiga 500 which has badly suffered from the same fate

Bryce.

Oh dear friend, don't waste your time for that. Just get the RAM out and use it for a CPC-RAM-expansion 

[Bryce]

Well for a start, the RAM is soldered in, so it would be too much bother to remove it all for a CPC. Also these ICs are Dynamic RAM, so they aren't suitable for modern Static RAM solutions. And anyway, I want the expansion for my A500

@Gryzor: These batteries were still used right up to 486 Systems and are still used in some non-computer electronics, which is why you can still easily get them: http://www.reichelt.de/Memopuffer/3GP-60/index.html?;ACTION=3;LA=2;ARTICLE=2425;GROUPID=1016;artnr=3GP-60;SID=12Ts4Rkn8AAAIAACgHA2cb52c9983450769d5c77d2ed571415f39

Bryce.

[TFM]

For the A500? .... the Amstrad 500, ah, must have been that French model with 5.25" internal drive. Right? I saw a picture in the CPC Wiki 

[ralferoo]

For the A500? .... the Amstrad 500, ah, must have been that French model with 5.25" internal drive. Right? I saw a picture in the CPC Wiki 

And 0KB of memory...

[MacDeath]

an Amstrad CPC5256PLUS could have been great.

[Badstarr]

It's weird, about 8 years ago I saw a KC Compact machine at a car boot sale that looked like this PC! It wasn't the CPC clone but the name drew my attention as I had not seen a picture of the KC Compact CPC clone at the time. I didn't bother with it as it wasn't a machine that I was interested in once I had confirmed it was not a "CPC" . It was either a 286 or a 386 according to the rather poorly written instruction manual that came with it.

[Gryzor]

I did a brief looking around, found no PC KCCs... well, maybe for the best I would probably have bought it for the novelty factor if the price was right, but I would also mot probably have regretted the space it was taking up...