tvp5150 active video detection

3.21.47 Interrupt Status Register B

H/V lock changed can tell you if there is camera in and H/V sync locked.

BR,

Eason

I'm running embedded sync, i.e. no H/V-sync, will that still work?

Hi Embedded Sync you talked about is for the output data.

The H/V lock status is for the input video.

BR,

Eason

Pin 27 can be configured to generate a hardware interrupt signal which goes active whenever the input video status changes.

Please search for "interrupt" in the datasheet for more information.

BR,

Steve

it is configured indeed and Pin27 is connected to a GPIO on my host CPU, #27 is active low which is the recommended default setting on example 1 in TVP5150 doc.

if I intend to use this pin to tell if a valid video signal presents at Video input port:

1. which bit I should use for register 0x1D (Interrupt Enable Register B)

2. is active_low here meaning level trigger or falling-edge trigger?

3. if pin#27 becomes active low(i.e. interrupt happened), do I must clear the interrupt status(register 0x1C) for the next interrupt?

Thanks a lot!

The best interrupt to use is probably bit 1, H/V lock changed.

Note this bit indicates a CHANGE, so this will also trigger when lock is acquired. You should then read the lock status to determine if the interrupt is triggered by a loss of lock or an acquire of lock (status register #1, 88h)

The interrupt is a level and needs to be cleared by writing a '1' to bit 1 of interrupt reset register B (1Ch)

BR,

Steve