[Coco] Last video I promise... :)

Luis Antoniosi (CoCoDemus) retrocanada76 at gmail.com
Fri Dec 5 12:32:13 EST 2014 

No I'm not planing in removing them. I'm just explaining what could be done
:)



Luis Felipe Antoniosi



On Fri, Dec 5, 2014 at 12:27 PM, S Klammer <sklammer at gmail.com> wrote:

> Luis, I'm sorry to hear that you are considering/intending to remove the
> artifact ability.
>
> I've not received my "surplus" funds to purchase the needed pieces yet to
> build one myself; but, would a shielded cable to bypass the possible noisy
> traces help?
>
> Shsin
> On Dec 5, 2014 11:09 AM, "Luis Antoniosi (CoCoDemus)" <
> retrocanada76 at gmail.com> wrote:
>
> > Ok finally my mules decided to arrive and I assembled one for me.
> >
> > I don't get the noise you have there, but I noticed there is a small
> noise.
> > My prototype doesn't have this. The culprit is the VGA ouput. In my
> > prototype I have placed them far away from the input lines. But in the
> new
> > design i tried to make things more compact and I sucked on this :P
> >
> > Well, modifying the FPGA I have reduced the amout of noise changing the
> > input/output currents. You can check whether your noise is the vga by
> > doing:
> >
> > screen 80
> > cls 4
> > dir
> >
> > Check if the noise increases as the amount of the text on screen also
> > increases. In your video, when you blast the trimmers, I can clearly see
> > blanking lines waving, so it must be it.
> >
> > How to solve this completely ? Redesign the board ? Using a faraday cage
> ?
> >
> > Update your repo and try the new version. it might help.
> >
> > Regarding the colors, you may notice that some colors have a "noise
> > pattern" on that, look that this partern doesn't run, it has some
> > flickering but they stay put.
> >
> > This is not external interference, it's merely slack time that is
> affecting
> > how the colors are digitized. Let's say: the altera is running the code
> at
> > the limit of it's speed. This cause the code to get out of sync with the
> > clock and then, the color is digitized in the wrong level of the DAC, or
> it
> > didn't have time enough for the differential to change its value. Solving
> > this is much more difficult.
> >
> > The first thing is to remove and simplify the code, this means no more
> > artifacting colors, and other stuff. This would help getting a stable
> > timing though.
> >
> >
> >
> >
> >
> >
> >
> > Luis Felipe Antoniosi
> >
> >
> >
> > On Fri, Nov 28, 2014 at 11:11 PM, Richard Goedeken <
> > Richard at fascinationsoftware.com> wrote:
> >
> > > Hi Luis,
> > >
> > > Here are new images of the board and the video output:
> > >
> > > http://www.fascinationsoftware.com/media/rgb2vga/IMG_9763.JPG
> > > http://www.fascinationsoftware.com/media/rgb2vga/IMG_9766.JPG
> > > http://www.fascinationsoftware.com/media/rgb2vga/IMG_9768.JPG
> > > http://www.fascinationsoftware.com/media/rgb2vga/IMG_9770.JPG
> > > http://www.fascinationsoftware.com/media/rgb2vga/IMG_9775.JPG
> > >
> > > Unfortunately, grounding the connector shield didn't fix the noise
> issue;
> > > it's
> > > still there like before.  I'll have to consider all of the various
> > devices
> > > that are plugged in, and see if there is a ground loop there somewhere.
> > I
> > > am
> > > using 1% resistors for the 75 ohms.  Do you have any suggestions for
> > > improving
> > > the color fidelity?  What changes did you make to the FPGA code to
> > > customize
> > > it for your particular Coco?
> > >
> > > Richard
> > >
> > > On 11/28/2014 05:55 PM, Luis Antoniosi (CoCoDemus) wrote:
> > > > now I saw the video.
> > > >
> > > > First question: which program is that ? How do I get it. It's very
> nice
> > > for
> > > > testing the colors.
> > > >
> > > > Second, can you take a picture of your board ? bottom/top ?
> > > >
> > > > There is indeed a noise band rolling. I don't get these, but my board
> > > from
> > > > osh park DIDN"T ARRIVE YET. I takes a month to cross the canadian
> > border.
> > > > Dude they must put them on the back of mules. Cannot explain that.
> > > >
> > > > Then check the grounding. Make sure everything is grounded from coco,
> > > > altera and the monitor. (make sure the outer shell is grounded as I
> > > said).
> > > > It's getting there, the image is pretty good already.
> > > >
> > > > Also, do you have MPI or any other device  on your coco ? I'm always
> > > > testing with either superIDE or CocoSDC but never mpi. Just try the
> > coco
> > > > without any device and check the 32 and 80 columns screens:
> > > >
> > > > width 80
> > > > 10 for n=32 to 255
> > > > 20 print chr$(n);
> > > > 40 next n
> > > >
> > > >
> > > >
> > > >
> > > > Luis Felipe Antoniosi
> > > >
> > > >
> > > >
> > > > On Fri, Nov 28, 2014 at 8:02 PM, Richard Goedeken <
> > > > Richard at fascinationsoftware.com> wrote:
> > > >
> > > >> Hi Luis,
> > > >>
> > > >> Thank you so much for designing the awesome video converter and
> making
> > > all
> > > >> the
> > > >> plans available.  I built one up yesterday and hooked it up to my
> Coco
> > > 3,
> > > >> and
> > > >> it works, but there is some noise in the video output and the colors
> > are
> > > >> not
> > > >> exactly right.  Can you help me get it working?
> > > >>
> > > >> I uploaded a video which shows the problems very well.  It's raw
> > mpeg2ts
> > > >> (AVCHD) at 1080i 60hz from my video camera; the file is about 131MB.
> > I
> > > >> didn't
> > > >> want to upload it to youtube which would crush the resolution and
> > frame
> > > >> rate.
> > > >>  You should be able to view it with VLC or mplayer or similar:
> > > >>
> > > >> http://www.fascinationsoftware.com/media/Coco3-RGBVGA.mts
> > > >>
> > > >> In the video, I turn the 10k potentiometer up and down to show how
> it
> > > >> affects
> > > >> the colors.  You can see that there are some rolling bands of noise
> in
> > > the
> > > >> brightness values of the pixels.  And many of the colors seem to be
> > the
> > > >> same
> > > >> shade.
> > > >>
> > > >> The test screen output (when the Coco is turned off) is perfect, so
> > the
> > > >> problem is with the input section.  I wasn't sure exactly which
> build
> > of
> > > >> your
> > > >> FPGA code I should use.  And I've never used FPGA tools before, so
> > there
> > > >> was a
> > > >> little bit of a learning curve in installing the tools and using
> them.
> > > >> But I
> > > >> ended up with the latest git clone from the github repo (as of
> > > yesterday),
> > > >> and
> > > >> I used the Quartus programmer tool to write the output_file.jic into
> > the
> > > >> serial eeprom loader memory.  Should I have used a different
> version?
> > > Do I
> > > >> need to compile the fpga code?  It looks from your repo that you
> > update
> > > the
> > > >> SOF and JIC files with every commit, so I assume that means I don't
> > > need to
> > > >> compile the project if I don't make any of my own changes.
> > > >>
> > > >> Any ways, thanks again for this great product, and I hope I can get
> it
> > > >> working
> > > >> here.
> > > >>
> > > >> Richard
> > > >>
> > > >> On 11/11/2014 05:03 PM, Luis Antoniosi (CoCoDemus) wrote:
> > > >>> It's all here:
> > > >>>
> > > >>> https://sites.google.com/site/tandycocoloco/rgb2vga
> > > >>>
> > > >>>
> > > >>> Luis Felipe Antoniosi
> > > >>>
> > > >>>
> > > >>>
> > > >>> On Tue, Nov 11, 2014 at 7:23 PM, Mark McDougall <
> > msmcdoug at iinet.net.au
> > > >
> > > >>> wrote:
> > > >>>
> > > >>>> On 12/11/2014 2:42 AM, Luis Antoniosi (CoCoDemus) wrote:
> > > >>>>
> > > >>>>  Let's say: everytime you add a switch and a if condition the code
> > > >> splits
> > > >>>>> in
> > > >>>>> two and the fpga seems to execute both. It's all parallel. It's
> > hard
> > > to
> > > >>>>> understand...
> > > >>>>>
> > > >>>>
> > > >>>> Is the code public? I can attempt to explain it if you're
> > interested?
> > > >>>>
> > > >>>> Regards,
> > > >>>>
> > > >>>> --
> > > >>>> |              Mark McDougall                | "Electrical
> Engineers
> > > do
> > > >> it
> > > >>>> |  <http://members.iinet.net.au/~msmcdoug>   |   with less
> > > resistance!"
> > > >>>>
> > > >>>> --
> > > >>>> Coco mailing list
> > > >>>> Coco at maltedmedia.com
> > > >>>> https://pairlist5.pair.net/mailman/listinfo/coco
> > > >>>>
> > > >>>
> > > >>
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> > > >>
> > > >
> > >
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