I have spent some time looking at the movie-capture task on the A620 and S95.
Whether synch can be adjusted or not, we need some way of indicating it.
One method is to monitor the A/V outputs, extract the frame-synch pulses and measure the time difference.
Problem is, the LCD will blank.
Maybe the memory-mapped I/O register can be overriden or there is another function that ensures the LCD stays on ?
A second method, is to flash the autofocus led every time the task is entered.
(toggling is easier and maybe better as you get a signal with equal high and low times).
On the A620, a jump to a function that uses debug_led() will flash the led as soon as the dial is in the movie position.
This is useful because the user can see the amount of synch without having to start recording.
On the S95, and presumably some other cameras, a jump to the led function as soon as possible at the task entry only flashes the led when recording.
Is it likely that some other function is called every 1/29.97 seconds when the switch is in the movie position and the led toggling could be done there ?
(Some cameras have a momentary movie button of course.)
Surely the movie task is always running when the switch is in the movie position ?
@reyalp
You once posted comments about why you cannot always simply include a "BL" to your own routine.
Can you remember what you said ?
When do we have to save registers and how do we know which ones ?
