Is the RCA unit bi-directional?



  • Can the RCA unit receive data as well as transmit? I noticed a few extra components on the board that might prevent it from doing so.



  • It all depends on your IO configuration. The unit itself contains a 75Ω Resistor to GND and a 4.7Ω to the GPIO pin. And of course a switch to choose from the both GPIO on the groove. If you use it as an input the 75Ω will pull-down the port. The current draw on high signal will be I= U/R = 3.3V/75Ω = 44mA!

    See schematic on https://docs.m5stack.com/en/unit/RCA
    In the schematic the 4.7Ω Resistor is labeled L2 which seems to be wrong and should be R2 (or R3 as the 0Ω Bridge is still R2). In the photos it is a resistor (4R7 printing on it).



  • So it can’t receive data, right?



  • @hwtaro9 Well, it is intended to transmit video generated from the M5Stack to a monitor.
    The RCA unit "could" receive if there was a video decoder in the M5Stack, which there is not.
    The unit itself is a passive connector only.