Software to test the screen.

[||C|-|E||]

Hi guys!

Since I am in the process of adjusting my screen, I would like to know if there is something like a software for this that can be used with our CPCs. Ideally, it would use overscan, because it needs to be able to display the image all over the screen, ignoring the border. At least, the soft should allow you to display pure red, pure green, pure blue, pure white and something like this grids to adjust convergence. The white grids would be in Mode2.

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Of course, coding the part that just displays the colors is trivial in basic, but I never worked with overscan in before to display something like the grids, that is why I am asking if somebody knows about a specific software. I could try to do it myself with a little bit of ASM but my knowledge in this regard is quite limited, so a helping hand would be extremely welcome  Alternatively, I could always use an image visualizer that allows overscan and prepare some images from the PC. This would be equally useful if you know one.

Thanks!

[PulkoMandy]

I think ConvImgCPC (CPCRULEZ > EMULATION > UTILITAIRES > CREATION GRAPHIQUE - ConvImgCPC{5}) can be used to convert pictures easily into a loadable file that will setup and show them in fullscreen. Be aware that using this requires erasing the system area (because you need a contiguous 32K area for the picture data) so there is no way back to BASIC.

[||C|-|E||]

Yes, that would be viable an alternative  . However, I was thinking more in a program that lets you press some keys and switch between screens, this would save me some resetting.

[demoniak]

With ConvImgCpc V0.17 you can load an overscan picture in basic:
- You should check "Code->img" before saving the converted picture
- In basic, you can do this to display picture :

Code Select Expand

openout"d":memory &1FF:load"picture.scr",&200:call&811
This will load, display the picture, and wait for a key pressed

[||C|-|E||]

Awesome, thank you! I will make a little program to test these things then     

[Bryce]

I wouldn't advise using overscan, or at least offer non-overscan screens too. The tests need to show that the screen is working within its normal limits.

Bryce.

[||C|-|E||]

That is certainly true. My idea is to use overscan and, in the image, mark the normal limits as well. That way I should be able to control both things at the same time . If the thing works well and turns out to be useful maybe somebody will benefit from the program in the future as well .

[Bryce]

Yes, but the monitor may perform differently in overscan than it does in standard mode. By overscanning it, you are changing how the electronics are functioning.

Bryce.

[||C|-|E||]

Huum... I will make two versions then 

[MacDeath]

Basically you need a diaporama of Fullscreen things that enable to check the display ?

I guess some grids may be numbered as well.

[||C|-|E||]

I was thinking to display the classical usual things to check geometry, convergence, purity... plain pure colors, some grids and a few simple geometric figures

[||C|-|E||]

I was trying and the setup seems to work  . This is all overscan, I still did not do the other version (but I marked the usual border positions with some black squares). Basically, what I see is a deformation plus color blotting in the upper right corner, the other parts seem to have a perfect geometry.

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On the bright side, the lines in the screen are straight now and it seems that I adjusted the V-size in a proper way. The H-size is almost fine too, just those few pixels I noticed in before.

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So, I am quite happy with the set of tests. I do not like that corner much, though, let´s see is the convergence strips fix the thing. I saw that a magnet can correct the problem with the purity but the distortion is a different thing. Good news is that the distorted area only appears if you overscan. This means that just color correction should be enough for most games and applications . I could also recap the guy but knowing the capacitors to change is a bit tricky. Oh well, one step at a time.

[ZbyniuR]

I made once something like this for friend.
3 screens change by space: 

27 colors at once,
test screen similar like on TV stations,
and frame on overscan with narrow stripes.

Now you can tuning. And enjoy cherry beauty.

PS.:  ECM.PAL made by AST.

[||C|-|E||]

Thank you very much! This set of tests will complement mine in a beautiful way .  I still need to wait a few days to do the real adjustments though, some friends are at home this easter and it does not seem a great idea to mess with a crt in the living while they are around!

[seanb]

That sounds like the ultimate drinking game to me.

[||C|-|E||]

LOL

[Audronic]

@||C|-|E||

Awesome, thank you! I will make a little program to test these things then 

Did you ever make the test program and release it ?

I would be interested.
Thanks  Ray

[khaz]

I've said it elsewhere but 240p test suite is a great collection of tools to test and calibrate your display, and it's available on most consoles. I would love to see it ported to the CPC computers for people who don't have a mean to connect a console to their Amstrad monitor.

[||C|-|E||]

@||C|-|E||
Did you ever make the test program and release it ?

I would be interested.
Thanks  Ray

I made some tests, yes, but I did not release them. I can prepare a couple of DSKs if you are interested 

[Audronic]

@||C|-|E||

I made some tests, yes, but I did not release them. I can prepare a couple of DSKs if you are interested 

Yes i would like to have them.
I have just setup a HDMI Monitor for my 6128 and am not sure of its alignment.

Thanks in advance


Ray

[||C|-|E||]

So here is the DSK. I put the more useful tests (in my hands) inside one single floppy  . There are a few BASIC programs in there:

- FSCOLORS.BAS generates full screens that are pure green, red, blue and white. You can change between them with the SPACE bar. I used this one mainly for the purity adjustments (centering the green and so on).

- RED.BAS, GREEN.BAS and BLUE.BAS generate overscan grids of those colors. I marked the positions of the usual border as little black squares.

- GRID.BAS displays a pattern of lines and dots on the screen that you can use to align your image.

You probably will not need to use FSCOLORS.BAS but the others can be useful. I hope it helps!

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[Audronic]

@||C|-|E||


Thanks I will try It.
Ray

[Audronic]

Thanks just what i wanted.


Ray

[Kris]

Great idea to release those few .DSKs; thank you !

[||C|-|E||]

Great to see that they are useful!