This isn't worth it!

I caught the sarcasm. However, I was saying that if you know of something specific that you believe people are trying, and, in your example, uses resistors, perhaps you should tell us about it, since you know it only "works" rather than being properly functional.

I know of no way to comply with RS232 without a negative supply. You apparently think there are methods commonly applied that "work" using just resistors. I don't disagree. I just suggested you be specific, rather than providing the usual "handwave." That would serve as a useful caution to the uninformed.

RE