Detecting PAL vertical sync with PIC

[Quack]

Hi,

What would be the simplest way to detect the vertical sync with a pic
(16f628) chip on a PAL video signal ?

Everything i google up is quite complex as it does a whole lot more than i
want. The only thing i care about is to trigger an event for each vertical
sync that passes my way.

Any suggestions would be great

Alex.

 

[Don Pearce]

On Thu, 3 Mar 2005 11:43:39 +0200, "Quack" <alex+google@vuetec.com>
wrote:

Hi,

What would be the simplest way to detect the vertical sync with a pic
(16f628) chip on a PAL video signal ?

Everything i google up is quite complex as it does a whole lot more than i
want. The only thing i care about is to trigger an event for each vertical
sync that passes my way.

Any suggestions would be great

Alex.

Don't even go here. Just get yourself a sync separator chip like an
EL1881 and the whole job is done for you.

d

Pearce Consulting
http://www.pearce.uk.com

 

[martin griffith]

On Thu, 3 Mar 2005 11:43:39 +0200, in sci.electronics.design "Quack"
<alex+google@vuetec.com> wrote:

Hi,

What would be the simplest way to detect the vertical sync with a pic
(16f628) chip on a PAL video signal ?

Everything i google up is quite complex as it does a whole lot more than i
want. The only thing i care about is to trigger an event for each vertical
sync that passes my way.

Any suggestions would be great

Alex.

http://www.national.com/pf/LM/LM1881.html#Datasheet

pin 3



martin

"An eye for an eye makes the whole world blind"
Gandhi

 

[Luhan Monat]

Quack wrote:

Hi,

What would be the simplest way to detect the vertical sync with a pic
(16f628) chip on a PAL video signal ?

Everything i google up is quite complex as it does a whole lot more than i
want. The only thing i care about is to trigger an event for each vertical
sync that passes my way.

Any suggestions would be great

Alex.

I would seriously consider the above advice on the 1881 chip. However,
if you just *must* do it with a pic, here is one way...

Schematic: http://members.cox.net/berniekm/videodet.gif
Source: http://members.cox.net/berniekm/VDET3.SRC

Basically, detect the horizontal sync pulses and then look for the wide
ones that denote vertical sync.

--
Luhan Monat (luhanis 'at' yahoo 'dot' com)
"The future is not what it used to be..."
http://members.cox.net/berniekm