These are some photos from the wiring. Nothing special, just TX/RX to the TTL to RS232 board and 5V to it. Then the fader is 3.3V power/ground and the other wire to A0 input.
Hmm, I just see that the shadow doesn't let you see anything. The blue wire is connected to TX and white to RX
How can I use the RTS and CTS port? Should I just connect it with a digital port and send High? Or how does it works. It's plausible that the video mixer sees if a device is connected with the RTS/CTS.
Or should I connect certain pins from the connector?
Thanks for the help! I'm a really newbie in serial/RS232/arduino/IC stuff