[K0balt]

Yeah, good times. I just recently had one that was a really strong misdirection, ended up being 2 simultaneous other, non related things that conspired to make it look convincingly like my code was not doing what it was supposed to. I even wrote tests to see if I had found a corner-case compiler bug or some broken library code. I was half way through opening an issue on the library when the real culprit became apparent. It was actually a subtle bug in the testing setup combined with me errantly defining a hardware interface on an ancient protocol as an HREG instead of an IREG, which just so happened to work fine until it created a callback loop inside the library through some kind of stack smashing or wayward pointer. I was really starting to doubt my sanity on this one.

[foobarian]

> corner-case compiler bug

They say never to blame the compiler, and indeed it's pretty much never the compiler. But DNS on the other hand... :-)

[recursive]

Unless you wrote the compiler

[K0balt]

Yeah, it’s basically never the compiler. That’s how you know you are truly desperate… when you think you’ve eliminated everything else lol.

[throwup238]

The joys of modbus PLCs, I take it?

[K0balt]

Ah, yes. But a roll- your own device with C++ on bare metal, so lots more fun.

(we’ll need a few thousand of these, and the off the shelf solution is around 1k vs $1.50 for RYO )

By the way, the RISC V espressif esp32-C3 is a really amazing device for < $1. It’s actually cheaper to go modbus-tcp over WiFi then to actually put RS485 on the board like with a MAX485 and the associated components. Also does ZIGBEE and BT, and the espressif libraries for the radio stack are pretty good.

Color me favorably impressed with this platform.