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Re: Why did Woz use the long cycle?

Hi Ferdinand,
If I am not mistaken, by presetting VA to 1 instead of 0, you will skip the first entire horizonal line of output. If you want to play with phase shift, I think you need to play with horizontal output counter presets, but that will also shift the whole line of data. Of course you could stall the clock timing counter 2 clocks for every every horizontal line, but that has already been done for us. 

but I'm probably missing some aspect of what you are thinking about.

Regards,
Mike Willegal

ferdimh@gmx.de wrote:

On 5 Apr., 01:15, Mike Willegal <m...@willegal.net> wrote:


Hi Ferdinand,

I'm not exactly sure what you are doing with D13-6 or A8-14, but
I don't think that low-res graphics will work very well.  Every other
line will be phase shifted 180 degrees in relationship to the color
burst, resulting in alternating colors instead of a (more or less) solid
block of color.

I'm almost tempted to try removing the extra 2 cycles on an old scrap
board, just to see the effect.



You misunderstood me. The modifications I mentioned ARE to comensate
for the 180� phase shift every line.
I never mentioned how to remove the long cycle. One just needs to
force the COLOR DELAY' signal in the timing section high.


Also the extra 2 cycles brings the overall timing closer to NTSC's
standards for horizontal and vertical timing.



that's true, I forgot to mention it...


Regards,
Mike Willegal



Ferdinand Meyer-Hermann