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Does anyone have a suggestion as to a good description
of the composite and component waveforms for SD and
I have found some notes on the Internet but they all seem
to be missing bits or are in gawdy colours that are difficult
to read. I appear to have lost my BBC B course notes which
I think had a good description of the PAL waveform.
I am trying to implement a SD / HD test card generator on
an Altera FPGA development board. So I need quite detailed
- Charles G4GUO
The best I can find is.
http://www.pembers.freeserve.co.uk/Worl ... dards.html
It is suprising how little use much of the material on the internet is. I am sure
what I am looking for is out there somewhere.
It is the frame syncs I am having a problem with currently. My code generates
them but it is very complicated using state machines and I am sure there is a
simpler way to construct them.
3 free downloads from the ITU bookshop is broken at the moment.
- Charles G4GUO
Seems as if the ITU bookshop does not like Firefox.
I changed to IE and have been able to download BT.1700
I now have 2 downloads left.
This is the 625 system B frame sync structure:
http://www.pembers.freeserve.co.uk/Worl ... 25-PAL.pdf
All the other analogue systems are there too.
In the end I downloaded a copy of BT.1700 and have the
sync FPGA code done, I am just trying to figure out the
colour burst phase and blanking at the moment.
The field numbering is a bit confusing as they have
Field 1, Field 2 in one figure then field I, II, III, IV
in another and in one of the sets of notes they talk about
I think they mean
1 I 1
2 II 2
1 III 3
2 IV 4
1 I 5
2 II 6
1 III 7
2 IV 8
Well I hope they do!
I may be wrong!
Just need to design a fancy looking test card next. There is only about 120 kbits
of memory in the small FPGA so it will have to be something simple. Still it has
proved a good learning exercise and makes me feel confident in tackling a more
complex project next.
I guess most people use a P.C these days for their testcards/video effects.