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From: Roger on 20 Feb 2005 11:47
I'm about to start a project using SAA7113 and SAA7129 Philips devices. I've
so far not been able to find any useful application notes to provide advice
on how these devices should be connected and used. Does anyone have any
experience of using these components and maybe some application notes or
proven circuitry that they could share with me please?

TIA.

Rog.


From: Paul Carpenter on 20 Feb 2005 15:29
On Sunday, in article
<%a3Sd.1554$LR3.1228(a)newsfe5-gui.ntli.net>
enquiries(a)rwconcepts.co.uk "Roger" wrote:
>I'm about to start a project using SAA7113 and SAA7129 Philips devices. I've

A 9bit Y/C or CVBS input processor
and 8bit video encoder devices
both with I2C control

Both with support for all sorts of captioning, widescreen and ITU656 data
formatting.

>so far not been able to find any useful application notes to provide advice
>on how these devices should be connected and used. Does anyone have any
>experience of using these components and maybe some application notes or
>proven circuitry that they could share with me please?

There is a wealth of information in the data sheets for those devices,
including device circuits, however though do assume a few things you
understand first:-

1/ Working with video (NOT PC graphics)

2/ Digital video standards

3/ What your system is doing.

I would suggest you read this book first

Video Demystified
A Handbook for the Digital Engineer

By Keith Jack of (then) Brooktree
ISBN 1-878707-09-4

These sorts of devices are not a general learner part to get to grips
with understand digital video, its standards and system design for
video processing.

I do assume your are also going to have some frame stores and processor
control to interface with these devices?

Your system could almost be passthrough between the two devices or have frame
stores or even hard disk drives or other digital video sources so no
simple appliction note or design beyond somebodys product details will
tell you a quarter of the design. Most of these products are likely to
be in cost competitive or markets of high competition who are not likely
to share the amount of knowledge required.

Consider that the book I mentioned is over 400 pages long and does not
give detailed hardware and software designs down to each resistro or line
of code. There are lots of block diagrams, standards and timing discussions.

--
Paul Carpenter | paul(a)pcserviceselectronics.co.uk
<http://www.pcserviceselectronics.co.uk/> PC Services
<http://www.gnuh8.org.uk/> GNU H8 & mailing list info
<http://www.badweb.org.uk/> For those web sites you hate

From: Roger on 20 Feb 2005 16:20

"Paul Carpenter" <paul$@pcserv.demon.co.uk> wrote in message
news:20050220.2029.306875snz(a)pcserv.demon.co.uk...
> On Sunday, in article
> <%a3Sd.1554$LR3.1228(a)newsfe5-gui.ntli.net>
> enquiries(a)rwconcepts.co.uk "Roger" wrote:
>>I'm about to start a project using SAA7113 and SAA7129 Philips devices.
>>I've
>
> A 9bit Y/C or CVBS input processor
> and 8bit video encoder devices
> both with I2C control
>
> Both with support for all sorts of captioning, widescreen and ITU656 data
> formatting.
>
>>so far not been able to find any useful application notes to provide
>>advice
>>on how these devices should be connected and used. Does anyone have any
>>experience of using these components and maybe some application notes or
>>proven circuitry that they could share with me please?
>
> There is a wealth of information in the data sheets for those devices,
> including device circuits, however though do assume a few things you
> understand first:-
>
> 1/ Working with video (NOT PC graphics)
>
> 2/ Digital video standards
>
> 3/ What your system is doing.
>
> I would suggest you read this book first
>
> Video Demystified
> A Handbook for the Digital Engineer
>
> By Keith Jack of (then) Brooktree
> ISBN 1-878707-09-4
>
> These sorts of devices are not a general learner part to get to grips
> with understand digital video, its standards and system design for
> video processing.
>
> I do assume your are also going to have some frame stores and processor
> control to interface with these devices?
>
> Your system could almost be passthrough between the two devices or have
> frame
> stores or even hard disk drives or other digital video sources so no
> simple appliction note or design beyond somebodys product details will
> tell you a quarter of the design. Most of these products are likely to
> be in cost competitive or markets of high competition who are not likely
> to share the amount of knowledge required.
>
> Consider that the book I mentioned is over 400 pages long and does not
> give detailed hardware and software designs down to each resistro or line
> of code. There are lots of block diagrams, standards and timing
> discussions.
>
> --
> Paul Carpenter | paul(a)pcserviceselectronics.co.uk
> <http://www.pcserviceselectronics.co.uk/> PC Services
> <http://www.gnuh8.org.uk/> GNU H8 & mailing list info
> <http://www.badweb.org.uk/> For those web sites you hate
>

Paul,

Thanks for the response. I'm familiar with the video standards and will be
using the 656 format to send data to an FPGA processing engine. Regarding
the Philips chips it's things like the need (or not) for a filter on the
7129 outputs, what happens to the LLC output from the 7113 when it doesn't
have any video input i.e. does it free run at 27MHz? I just trying to take
some of the risk out of my initial work. I've not found the device data
sheets that good to be honest with you.

Maybe I should have been specific with my initial post.

Regards,

Rog.


From: Peter on 20 Feb 2005 16:53
[snip]

> Thanks for the response. I'm familiar with the video standards and will be
> using the 656 format to send data to an FPGA processing engine. Regarding
> the Philips chips it's things like the need (or not) for a filter on the
> 7129 outputs, what happens to the LLC output from the 7113 when it doesn't
> have any video input i.e. does it free run at 27MHz? I just trying to take
> some of the risk out of my initial work. I've not found the device data
> sheets that good to be honest with you.
>
> Maybe I should have been specific with my initial post.
>
> Regards,
>
> Rog.

If you don't have video going in it doesn't put out a sensible signal. I
didn't bother to measure what it did put out because it was rubbish. The
setup is the tricky thing and I had a lot of fun with these chips. The
settings seem to go on forever and if you poke one bit of the timing another
bit will need opposite tweaking. I'm not the hardware designer, I just
suffered with the software. The circuit is not complicated and most of the
clever stuff is in the settings. I recall that there was a magic resistor on
the 7129 that wasn't documented but if you missed it off then the composite
video output didn't work. The designers added low pass filters on all the
outputs consisting of an inductor and a few other bits in a simple network.

Peter


From: Roger on 20 Feb 2005 17:36

"Peter" <moocowmoo(a)newprovidence.demon.co.uk> wrote in message
news:cvb1pr$g9c$1$8300dec7(a)news.demon.co.uk...
> [snip]
>
>> Thanks for the response. I'm familiar with the video standards and will
>> be using the 656 format to send data to an FPGA processing engine.
>> Regarding the Philips chips it's things like the need (or not) for a
>> filter on the 7129 outputs, what happens to the LLC output from the 7113
>> when it doesn't have any video input i.e. does it free run at 27MHz? I
>> just trying to take some of the risk out of my initial work. I've not
>> found the device data sheets that good to be honest with you.
>>
>> Maybe I should have been specific with my initial post.
>>
>> Regards,
>>
>> Rog.
>
> If you don't have video going in it doesn't put out a sensible signal. I
> didn't bother to measure what it did put out because it was rubbish. The
> setup is the tricky thing and I had a lot of fun with these chips. The
> settings seem to go on forever and if you poke one bit of the timing
> another bit will need opposite tweaking. I'm not the hardware designer, I
> just suffered with the software. The circuit is not complicated and most
> of the clever stuff is in the settings. I recall that there was a magic
> resistor on the 7129 that wasn't documented but if you missed it off then
> the composite video output didn't work. The designers added low pass
> filters on all the outputs consisting of an inductor and a few other bits
> in a simple network.
>
> Peter
>

Peter,

Thanks for that. The "magic resistor" would sound really amusing if it
wasn't so important to the operation of the device. If you recall any more
detail I'd obviously be interested to hear.

Thanks again,

Roger.


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