Please forgive my ignorance, I'm a software programmer who is new to the electrical and hardware side.
Our Panasonic HS300G video switcher has a Tally connector. Below is the pin diagram and circuit diagram.
Pin 1-6 are for telling me which Camera input is active (Camera 1-6).
Using a Raspberry Pi 3, I need to be able to detect which pin is "active", and my software will then use that to run a software-based tally system.
I've been trying to research as much as possible myself to understand how "open collector outputs" work, but I'm still confused, and I don't want to fry anything on this video mixer by sending 3.3V to a wrong pin.
Would this design work as follows?
- Attach Pin 9 to GROUND on the Raspberry Pi.
- Attached Pin 1-6 to 6 individual GPIO pins set as "input" on Raspberry Pi
- Send 3.3V from a Raspberry Pi GPIO to Pin 7.
- Result: My GPIO "input" pins (1-6) will receive 3.3V whenever the corresponding camera input is selected. This will give the GPIO a "high" reading and my software will know that camera is active.
I would like to test this theory but I can't afford to send too high voltage and mess something up on this mixer! Please help me understand what is going on here, really appreciate it.