I've bitched and griped about the frequent calls for persons presenting queries related to using what they've already got on hand to change their core concept in favor of a current-generation device. .... of course, admit that, starting from nothing, would find using modern devices a good solution to many problems.
I would, were I the owner, hate to 'fear' to have someone graduating today do something to a product with a 8255 15 years from now. Using "current-generation devices" is more an issue of future ability to mainatain than anything else. Also, I find it ridiculous that some "educationl institutions" (NOTE THE QUOTES) teach with boards with 8255s on them.

The O/P has said he is a hobbyist, and, as such, it's unlikely he'd buy a multi-k-$ compiler for his hobby project. Having him go through all the perambulations required to do what I suggested, to the end that he could compile a 'C' program and subsequently program it into his target environment would not provide him with the tools that he would receive if he bought the full-up tool suite, neither would it deprive the vendor of that software of a sale, because he'd never be able to justify such an outlay for his hobby project.
The above would be true if you had done this one-on-one; however, you have possibly "guided" some unscroupolous person that were otherwise "likely to buy a multi-k-$ compiler"

Erik