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

Luis Antoniosi (CoCoDemus) retrocanada76 at gmail.com
Fri Nov 28 23:37:39 EST 2014


The customization is about the front porch, the code now is pretty stable
to be generic. But yours seem to work. Steven Hirsch had to change on him.
He didn't report about noise. So I can't tell if is a particularly from
yours or if this board has indeed noise. Until my mules decide to cross the
border I can't help you on this.

BTW, Steven has found out theat the correct values for the sync resistors
are 47 ohms instead of 82. I doubt this could be the source of problem.

You don't need the LM1881, the 680K and the 2 caps if you're not planning
to connect any other computers on it.

The scalines help improve the colors. You may turn them on, use a dip
switch. I have changed the dip switches, the scanline is now the label
shrink.

You don't have another coco to test right ? Also, how long is your cable
from the coco3 ? Is it shielded ? Do you have anything else that could be
potentially noisy ? Tried connecting the altera's usb cable in a different
power source, like iphone or samsung usb chargers ?

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
> >>>>
> >>>
> >>
> >> --
> >> Coco mailing list
> >> Coco at maltedmedia.com
> >> https://pairlist5.pair.net/mailman/listinfo/coco
> >>
> >
>
> --
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>


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