6128+ on a 17" VGA Monitor.

[CraigsBar]

Hi,


As I am sure you will recall I have had a fair few CPC Monitor failures on my 6128+. In light of these I have until recently been using a 21" CRT telly. Not ideal as it is too HUGE.


I therefore thought that a better solution must exist. PC monitors are freely available where small CRT tv's with Scart and Stereo sound are not so searching on Ebay I found the follow, and at under €30 I decided it was worth a shot.


http://www.ebay.ie/itm/250632127109?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1497.l2649#ht_3389wt_1174


Now by connecting only 4 wires (Red, Blue Green and Sync) from the DIN Output on my Plus to this board and plugging in a set of redundant PC Speakers I have a Fantastic CPC screen on a 1024x768 17" monitor.


So far I have tested the following software.. Mostly successfully


Prehistorik II - Perfect (in both Plus Enhanced and Normal 128k modes)
Batman Forever - Perfect
Super Caldron - Special mode 4 needed or else the screen goes all 'Jumpy' on diagonal movement otherwise perfect
Symbos2 - Perfect


The only failure to report so far is EdgeGrinder which forces the card to jump input modes as soon as the scrolling starts. But as horizonatal shooter are not generally my thing this is no issue really.


All Plus carts tested to date work perfectly - Pang, Switchblade and Plotting never looked so good.

If there is anyone else considering one of these cards, I am more than willing to test specific games/software.


Regards


Craig.

[Bryce]

This is perfect for the CPC and most other 8/16-Bit machines. I use a very similar circuit and I think there are others here that use exactly this device. The only problems that occur is when a game or demo uses frequency switching to create certain effects.

Bryce.

[Ynot.zer0]

I use one of these for my 464 and 6128.  It works great.  As Bryce says there are the odd demo/game that doesn't display properly, but most of what I've tested work okay.

[00WReX]

Thanks for the info guy's...I have been thinking about this for a while as I was recently given a 17" 4:3 LCD monitor.
Did not really have a use for it other than the CPC's, so based on your comments above I just ordered one.
Probably be a week or two until it arrives so I will be interested to see how it goes.

Cheers,
Shane

[Garrettimus]

Do you guys know if that converter works with a regular 6128?

[Garrettimus]

I have another question: do you know whether or not the 6128 has "colour composite video" out of the SCART connector? I found this somewhere: Composite video output ground (pin 19 ground) Pin 18.

[MacDeath]

A CGA to VGA converter ?

this exists ? it is cheap too ?

nice then...

I mean, the Amstrad CPC is basically a modded and better CGA.

[robcfg]

I have another question: do you know whether or not the 6128 has "colour composite video" out of the SCART connector? I found this somewhere: Composite video output ground (pin 19 ground) Pin 18.

As far as I know, no. The CPC only outputs RGB, but the SCART connector has pins available also for composite video and super video signals.

[MacDeath]

The only failure to report so far is EdgeGrinder which forces the card to jump input modes as soon as the scrolling starts. But as horizonatal shooter are not generally my thing this is no issue really.

so some CRTC tricks (or any kind of trick ?) may be prone to mess with the display through this card ?

Anyway, where is the cheaper supplier for this ?


I found these one :
http://www.jammaboards.com/store/cga/ega/yuv-to-vga-converter-pcb-gbs-8220/prod_291.html

http://cgi.ebay.fr/ws/eBayISAPI.dll?ViewItem&item=250886593406

what else ?

[Bryce]

The CPC outputs two different signals: Black and White Composite (Lum) and RGBS Red/Green/Blue with Composite Sync. The Composite in CSync means the tha Horizontal and Vertical Syncs are mixed into one signal.
When connected to a SCART socket you are using the RGB and CSync, connecting the Lum Composite would only produce a black and white picture. To get S-Video you would need to split the Y and U components into separate signals for each colour, which is what my S-Video adapter does: http://www.cpcwiki.eu/index.php/RGB_SVideo
CGA is a completely different signal, where the RG and B are digital signals which can only be on or off with a separate "Brightness" signal so that each of the RG and B have 3 possible values. The CPCs RGB is analogue like VGA.

Bryce.

[00WReX]

Still waiting for mine to arrive...I will be using it on regular CPC's no Plus for me...

Some info on Octoate's website...

http://www.octoate.de/wp/articles/connect-cpc-to-vga-display/


Cheers,
Shane

[Bryce]

so some CRTC tricks (or any kind of trick ?) may be prone to mess with the display through this card ?

Anyway, where is the cheaper supplier for this ?


I found these one :
http://www.jammaboards.com/store/cga/ega/yuv-to-vga-converter-pcb-gbs-8220/prod_291.html

http://cgi.ebay.fr/ws/eBayISAPI.dll?ViewItem&item=250886593406

what else ?

The cheapest seems to be ebay. Depending on the exchange rate it might be better to get one from the UK. The German one cost €26.99 + €5 postage [ebay]250921932635[/ebay]. From Hong-Kong it's about €25 with free postage but you might get stung by Customs / Zoll / Douane depending on how strickt they are where you live.

Bryce.

[CraigsBar]

Do you guys know if that converter works with a regular 6128?

I see no reason why not, other than the Audio pins there is no difference between the plus and cpc outputs

[Ynot.zer0]

works fine for me on a basic 464 and a basic 6128... I used the instructions from octoate website (I cut up and old broken cable from old monitor, but am sure you can buy the same connectors online somewhere)

[00WReX]

Hi Guys,
My VGA adapter card arrived today, and as luck would have it I had the day at home because I had worked overnight.
Anyway I got to have a bit of a play with it and wired it up exactly as "Octoate" described on his website.

Immediately the screen worked but just needed a bit of tweaking to make it look better and fit the screen (tested it on a regular 6128).
I'm using an old 4:3 17" LCD screen that's not the best screen you will find (think it was an ex business screen so was on continuoasly for a few years I reckon. Anyway I was give it so no complaints.
I found exactly the same as CraigsBar with the game Edgegrinder but I tried a heap of other games & demos without an issue.
Funnily though, one game that did not go well was the old Ghost n Goblins...everything appears fine untill the screen scrolls during gameplay and the display the scrolls vertically and sometimes even goes to no signal before coming back...would be interested if someone else could try this game to see if they get the same. The only other game I noticed an issue on was Sub Hunter. The display jumps around while on the menu screen but is perfectly fine during gameplay.
The backtro demo works fine also. I probably tested around 20 to 30 games and all were fine, including some games that I though it may struggle with. As CraigsBar also said, if anyone would like a game tested just let us know.

The only slight issue I have being a bit picky is that the initial Amstrad blue boot screen has some fine vertical lines that are a little annoying, but as soon as that screen goes, during gameplay for example the screen looks great...quite impressive actually.

I'm not sure if the lines are some form of interference...I will look into that further.

A couple of things that I think would be good for users of this card is note what settings people are using and also indicate the type of display they are using it on.
Also a list of games that have issues would be good.
Also I notice that the board I received is a GBS 8200 v4.0 2011.08.15
It may be good to note what board people are using as maybe newer revisions may also work better (or not).

I do think for the price, you can't go wrong...

So to start, the list of games I noticed issues with are,
Ghosts 'n' Goblins (during gameplay)
EdgeGrinder (during gameplay)
Sub Hunter (during the Menu screen only)

Cheers,
Shane

[00WReX]

OK gonna respond to my own post here.
Just been playing around some more with the settings on the adapter and I reckon I have almost got it perfect with regard to the vertical lines I was seing on the boot screen.

There are two settings called "Clamp st" and "Clamp sp", I'm not even sure what they really do but the manual I found on the web said alway keep st less than sp...not overly helpful & the range for both is 0 to 99.
Played around heaps with them and eventualy hit the jackpot with 89 & 95...I think this value will almost be unique for different hardware (monitor).
But for anybody not totally happy with the look of the picture, have a play with the values...can always hit the default option if it gets worse.

Just looking at the boot screen now and it looks totally clean...I am impressed now, this little adapter is quite nice.

Cheers,
Shane

[Bryce]

Clamping in electronics usually refers to shifting or offsetting a signal from its zero crossing point, which would make sense for a TV picture signal, but I've no idea what the SP and ST means. Possibly Signal Peak and Signal Time or some other variable in the firmware? Either way, if it improves the picture then it's a winner. It is more likely to be related to the input source rather than the LCD display, so it might vary from CPC to CPC rather than for different LCD screens.

Bryce.

[MacDeath]

Have you tested some redimensionned/overscan screen games/stuff ?

Titan (a game from Titus) may be a suitable candidate to test.

It uses a 128x256 (mode0) sized screen and have an impressive multi-directional fast scrollings...


Anyway it would be great to understand why some of those games (G'N'G, and the last kooistra productions obviously) are prone to screw up.


Pehaps the way they manage the scrollings ? (fast hardware scrolling ?)

4/3 LCD screens... yeah, most of them are actually found in biznesses and offices...


I guess when those were available, they were still too expensive so most regular peoples still used their regular old cathodic monitor.

It's only when the flat screen technology got older and cheaper, and 19/10... that most peoples switched, so they simply skipped the Flat 4/3 era..

To be fair, good old Cathodic VGA could be quite awesome, fine pixels, nice contrast and clear animation.
Flat screen took some time to get up into such quality and to be fair i'm not even sure they did.


I mean, just try to look at a flat monitor with a slight angle, the colours are completely changed...
But it must be because mine is a cheap one to begin with...

the only actual advantage is that the monitor is no more cubic, so you can put it a bit farther from your eyes despite a small desk.

Oh, and transporting it is no more such a pain "im der Arsh".

[00WReX]

Hi MacDeath, yes agree with what you say.

Must admit, only intended trying the LCD just for the fun of it, getting the CPC working with something a bit more modern.
But after only a couple of day, it has impressed me enough to stay on the desk and the old CTM can have a rest 

Just tried the game you mentioned as I have never tried or played it before.

Titan (by Titus) ran absolutely perfectly, and yes, you can get some pretty fast scrolling happening and change of directions.
Was very smooth actually. Even you would probably be impressed with how well the old 4:3 LCD performed 
Tried a few other games that I thought may not go well, but also went perfectly...the games were Trantor, Zynaps & R-Type.

Cheers,
Shane

[MacDeath]

Anyway i'minterested too by this topic, I will certainly get a 4:3 VGA flat screen from my darling when she change her old PC into a portable one...