Understandig serial-communication

[Thomaskjosnes]

Hi,

I am ordering some parts for my motor-controller project, and am looking at the serial communication between openplotter/tinyplotter and the motor controller. Seandepagnier recomends optoisolators.

I already have some ILD213 Optoisolator Microcontrollers, but I suppose they are too slow? Could ADUM1201 work?

And then McNugget seems to use a Mini RS232 to TTL Converter Adaptor?

Could I in theory, with some risk, just cross both TX to RX + GND and 5v, or do I need some interpretating controller on one/both sides? Do the cables need some special shielding for these kind of signals?

Why would I use RS232 adaptor? Should I use it on both sides, reversed? Do I still need an opto-isolator?

My boat has all kinds of Silva Nexus NX2-instruments (also with multi-control and server with rs232 nmea PC-port), but no plotter or autopilot for now. Should i buy more adaptors/isolators to use for adding information about wind, position, heading, speed and so on to the openplotter?

Needless to say, I still do not know what I am doing, but I am eager to learn.

[ironman]

I'd keep it KISS, see this thread https://forum.openmarine.net/showthread....5#pid13665. Depends a bit on the length of your cables.

[seandepagnier]

you can proceed without isolation at your own risk but be aware of level translation since the arduino typically runs at 5v and the rpi at 3.3