right well i spent most of today with my LA on the serial link and made a bit of progress, i should have livestreamed it but didn't think about it at the time!
the link is RS232 at 9600bps 8/n/1, the protocol is simple, but more complex than i expected so it's work-in-progress. For example it takes 11 bytes from the paintbox to get the ramcorder to display a single frame. Even playing continuous video requires the paintbox to request every single frame in realtime.
the 323 frames limit looks to be hard coded into the paintbox software so probably no scope to expand it, i couldn't see anything that informs the paintbox the size of the storage.
the ramcorder can display and record not only individual frames but also individual fields of video, i spotted this in the protocol and verified it
to reply to your posts...
I assume the SDI signal is 576i and not 576p?
yes, the paintbox and ramcorder both are 576i. The interlace is entrenched in the paintbox design and i don't believe they ever offered progressive scan on this architecture.
looks like SDI on FPGA is possible, its a big document though!
we have SD-SDI running on a Cyclone 2 thanks to user OzOnE, again another unfinished project, maybe we'll brush the dust off it if i make more progress on the protocol
I would love to see the protocol deciphered, i think it would make a great video.
noted, once i make a bit more progress i will look at putting something together
On a side note I remembered about some cheap HDMI to SDI and SDI to HDMI convertors that I saw on eBay (mainly used in CCTV) they might be handy for this system to use on a modern screen and to record etc
thankfully i have a Blackmagic unit that will record SDI to a SSD as uncompressed video which can easily be converted on my PC. I also have a couple of really nice pro scalers and converters i picked up cheap off ebay, means i can convert pretty much any type of video in and out of the paintbox.