Automate Blackmagic Video Assist recording control via Stream Deck

[geerlingguy]

Here's my rough idea:

• Use either a Pico/Arduino over USB, or a prebuilt cable (some people mention "Applied Logic Engineering's USB to LANC cable ALE708" but that company seems defunct) for USB-to-serial communication with the Video Assist via its LANC port.
• Set up at least Record Start / Record Stop following these codes from the BMD forums.
• Tie in Record (ideally as a single toggle button) to my Stream Deck, so I can hit one button to turn on lights, and another to start recording.
• Bonus points for:
  • The Record button is a macro that also launches Sound Studio and starts recording there, for a backup audio track.
  • Use LANC (or just a software toggle) to determine status of 'rec'/'tally' light so I can trigger an HA automation to turn on a red REC light outside the office.

Some resources:

• The SONY LANC protocol
• LANC commands for BMCC
• USB to LANC Interface Adapter by Applied Logic Engineering
• Arduino LANC control article
• arduino_lanc_sample with LANC Plug diagram

Inspired by this tweet.

[witnessmenow]

Might be worth considering a wifi based Arduino like the esp32, you'd get the same USB functionality if that's the route you want to take, or alternatively (or both) host a webserver on it so you could control it over your network

[Giltvedt]

As I mentioned in my reply to you tweet.

I think you’re looking for this shield for Arduino: Blackmagic 3G‑SDI Shield for Arduino

I had similar ideas, like yours, earlier when they released this shield. Did a little research about LANC (same references you found), but never came around to it. Now I’m excited to see what you come up with, if you choose to use this shield.

[geerlingguy]

@witnessmenow - For this particular use case, it'll be a couple feet from my computer, so direct wire is preferred... but I do have a spare ESP8266 that I could use and see if I could make a more universal solution.

@Giltvedt - At $50 used or $100 new, it seems like that SDI shield might be a little overkill for me. Plus the LANC cable could be a bit more tidy on the desk (though I already have two HDMI cables and a mini XLR hanging off the side of the monitor...). But we'll see. I've never touched SDI before, might be interesting to take a look.