so ive been messing around with this for a few weeks now and i think im close but not quite there. basically i have an old Yaesu G-450A rotator and ive been trying to get a pi zero w to talk to the controller over serial so i can automate it from my logging software. the idea is to just have it track satellites automatically without me having to babysit the thing.

ive got a USB to serial adapter hooked up and i can see the port in linux just fine, and i wrote a little python script that sends the positioning commands — at least i think theyre the right commands, been going off an old PDF of the manual i found. sometimes it moves, sometimes it just... doesnt. no error, just nothing. im wondering if its a timing issue or if my baud rate is off or something. also not 100% sure the GS-232 command set is fully supported on this controller, the manual is kind of vague about it.

anyone gone down this rabbit hole before? im not opposed to just buying one of those commercial rotator interfaces but id rather figure this out myself if i can

yeah done almost exactly this with a G-450 about two years ago. the GS-232 support on those older Yaesu controllers is kind of half-baked — it responds to some commands and just ignores others with no feedback at all which is super frustrating to debug. what baud rate are you running? mine was defaulting to 9600 but the controller wanted 4800, took me embarassingly long to figure that out.

also the timing thing is real — you need a small delay between sending the command and expecting any movement, like at least 200ms or it just buffers weirdly. i ended up using a simple state machine in python with time.sleep() calls scattered around and that mostly solved it. not elegant but it works. if you want i can paste the relevant chunk of code, its not pretty but it does the job for basic azimuth tracking on FO-29 passes.

not sure about that specific rotator but i built something similar with an Arduino Mega driving an H-bridge for a homebrew antenna rotator — totally different situation i know but the serial timing headache sounds familiar. one thing that burned me was the pi zero's UART had hardware flow control acting weird, ended up just disabling it entirely in the config and things got way more stable. might be worth a shot if you havent tried it already.