Better VGA timing and localised keyboard layout for the ZX-Uno

Dudas, cuestiones, sugerencias y peticiones en general sobre el proyecto / Questions and requests about the project
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Eratosthenes
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Better VGA timing and localised keyboard layout for the ZX-Uno

Mensaje por Eratosthenes » 03 Ene 2018, 15:12

Hi everybody,

at first I wish you a happy new year.

Since I have "Just The Board" (ZX Spectrum Next) I know that much better VGA output is possible for an FPGA 8-bit computer than the ZX-Uno has.
Using V0.5 of the firmware 50Hz and 60Hz VGA is much better than what the ZX-Uno supports. Using the Next the display is "pixel perfect". All pixels nearly 100% fit to 4x4 pixels of the panel of the monitor. Using the Uno several pixels are somehow unbalanced. (Some pixels are smaller than others.)

So now my questions:
1: Is it possible to manipulate the VGA timing so that it better fits to my monitor?
2: Can I configure the keyboard so that it is more common to me? - I'd like to map several keys in an other way than they are now.

THNX 4 info.

MfG
der Eratosthenes
Nine out of ten voices in my head say: "You're not mad!" - The tenth humming the melody of Pong <click> ...

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desUBIKado
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Re: Better VGA timing and localised keyboard layout for the ZX-Uno

Mensaje por desUBIKado » 03 Ene 2018, 17:57

Hola Erathostenes:

Pásame por favor un fichero .TAP con la imagen de prueba que has usado y yo le saco una foto a mi monitor al que tengo conectado mi ZX-Uno por la salida VGA.

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Eratosthenes
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Re: Better VGA timing and localised keyboard layout for the ZX-Uno

Mensaje por Eratosthenes » 03 Ene 2018, 18:14

Hi desUBIKado,

english for me would be better as the translator (g**gle) doesn't manage to translate your post in a way that I can understand it... :(

*sorry for that* :(

MfG
der Eratosthenes

P.S.: I think it is about SCREENSHOTS...

This is how the Next looks.
hdmi_50Hz_07_001.jpg
"Something like this" (photo taken from V0.7 from the Next) is what the ZX-Uno looks on my VGA (an Eizo display)...
vga_50Hz_07_001.jpg
P.S.: This is how it looks like on my ZX-Uno
ZX-Uno_VGAdisplay02.jpg
ZX-Uno_VGAdisplay.jpg
Nine out of ten voices in my head say: "You're not mad!" - The tenth humming the melody of Pong <click> ...

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mcleod_ideafix
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Re: Better VGA timing and localised keyboard layout for the ZX-Uno

Mensaje por mcleod_ideafix » 03 Ene 2018, 20:12

VGA, as opossed to HDMI or DVI, doesn't carry pixel clock information, so the monitor has to figure it out. If the monitor can "talk" with the video controller (via DDC signals) to interchange information about supported resolutions and clocks, then a perfect image is possible on VGA. If not (which is the case in ZX-UNO, I don't know about the Next), the monitor has to be adjusted to match both the frequency and phase of the pixel clock, either by guessing it (auto adjustment option for most monitors) or by manual adjust.

So, it may happen that you have your monitor adjusted for the pixel clock of the Next, and haven't done the same for the Uno.

First, I'd suggest to update to the latest version of the Spectrum core (EXP25-20092017).
Second, if using ULA 128K timings, ensure that you have frequency option to -f1
And last: adjust your monitor to match clock phase. Horizontal size may need to be adjusted as well. The image you are using is very helpful for that, because any frequency of phase mismatch will show as vertical bands of varying width.
http://www.zxuno.com
ZX-Uno · Clon de ordenador ZX Spectrum basado en FPGA

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Eratosthenes
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Re: Better VGA timing and localised keyboard layout for the ZX-Uno

Mensaje por Eratosthenes » 03 Ene 2018, 20:20

Not sure if I've got the update (but I think so).

As mentioned: The timings the ZX Spectrum Next has in V0.5 is synchronized "perfectly well". So: Is there a possibility to configure VGA timings in a way that they are similar to the ones provided for the Spectrum Next?

And: Yes, I've synchronized the phase of the monitor. The "error" is more than two pixels wide. Phase errors usually are less than one pixel of the panel.
(One "Spectrum-" pixel you see in the screenshot usually is about four pixels of the panel.)

Have a look at the 2nd screenshot (V0.7) of the Spectrum next. The phase fits perfectly well. Just the pixels are drawn wrong. They do not have the right height ow width. It's the same with the ZX-Uno.)

P.S.: Off topic @mcleod_ideafix - Could you add the sync signal to green for RGB out at 16kHz?
As I've got an other Monitor (TV) that is able to display the ZX-Uno I've got an other problem. Without "sync on green" the RGB output for PAL is useless for me. :(
If you could add an option to add "sync on green" (this means horitontal and vertical sync) to the signal this monitor would work.

If so I wouldn't have any problems with VGA as I wouldn't use it... ;->>>
Última edición por Eratosthenes el 03 Ene 2018, 20:37, editado 1 vez en total.
Nine out of ten voices in my head say: "You're not mad!" - The tenth humming the melody of Pong <click> ...

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desUBIKado
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Re: Better VGA timing and localised keyboard layout for the ZX-Uno

Mensaje por desUBIKado » 03 Ene 2018, 20:37

Hi Erathostenes:

I show you some pictures take with my ZX-Uno. The monitor is a LG Flatron M1917A
20180103_202211.jpg
20180103_202340.jpg
20180103_202204.jpg
20180103_202325.jpg
20180103_202240.jpg

Core: EXP25-070917
Firmware: 0.63

:zxuno: Rulez !!! :o
Última edición por desUBIKado el 03 Ene 2018, 20:41, editado 2 veces en total.

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Eratosthenes
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Re: Better VGA timing and localised keyboard layout for the ZX-Uno

Mensaje por Eratosthenes » 03 Ene 2018, 20:38

Is this VGA out or RGB (PAL)?

THNX 4 the info.

P.S.: By the way: It looks good! Exactly the way I would like it on my monitor... ;->

--
I just checked. - I don't have the latest core.

Does EXP25-070917 fit to my Uno? - It's one of these <klick>...
Nine out of ten voices in my head say: "You're not mad!" - The tenth humming the melody of Pong <click> ...

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desUBIKado
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Re: Better VGA timing and localised keyboard layout for the ZX-Uno

Mensaje por desUBIKado » 03 Ene 2018, 20:46

It's VGA. The image output is superb.

Donwload core EXP25: http://svn.zxuno.com/svn/zxuno/cores/sp ... ECTRUM.ZX1 [User: guest / Pass: zxuno]
Última edición por desUBIKado el 03 Ene 2018, 20:51, editado 2 veces en total.

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Eratosthenes
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Re: Better VGA timing and localised keyboard layout for the ZX-Uno

Mensaje por Eratosthenes » 03 Ene 2018, 20:49

Really nice. - How can I get the latest core for my Uno?

I think this is the reason for my "display issue"... :D

P.S.: As I've seen the password... (*sorry to desUBIKado) I've updated the core. - This didn't fix the VGA issues. :(
Nine out of ten voices in my head say: "You're not mad!" - The tenth humming the melody of Pong <click> ...

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mcleod_ideafix
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Re: Better VGA timing and localised keyboard layout for the ZX-Uno

Mensaje por mcleod_ideafix » 03 Ene 2018, 21:56

Eratosthenes escribió:As mentioned: The timings the ZX Spectrum Next has in V0.5 is synchronized "perfectly well". So: Is there a possibility to configure VGA timings in a way that they are similar to the ones provided for the Spectrum Next?
Next HDL sources are not available, so I don't know what timings it uses.
Eratosthenes escribió:P.S.: Off topic @mcleod_ideafix - Could you add the sync signal to green for RGB out at 16kHz?
I don't know if I can add it without breaking compatibility with other TVs that expect a blank signal on R,G and B during the blanking period. I will put it on my to-do list :) May I count with you for testing this feature, I guess ;)
http://www.zxuno.com
ZX-Uno · Clon de ordenador ZX Spectrum basado en FPGA

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