the html code is a copy and paste from "komposer" a free html editor I found on the net , its really just what you did with an input field MyInput added in to a form and levered into your setup .
it does nothing useful just demonstrates sending data from the browser back to the pic. it works ok

if have stepped up to a pic18f45k20 so resources aren't an issue yet , biggest problem is if a connection is made while you are serving a page the incoming link request just stops everything dead .
and if you hit the refresh on the browser before current request (same connection ) is dealt with it all comes to a crashing halt.

parsing the data on the fly is a bit tricky if you are looking for multiple keys eg in the server loop I am looking for ,"busy" , "OK" and "MyInput" and trying to respond appropriately ,
I think I need to watch for "'Link", "Unlink" and "Error" too. I found it easier to swallow the lot and then pick the good bits out (a bit crude I admit but I'm looking at proof of concept here)

I'm not sure about the "channel" thing looking on the salea all link requests are ch 0 so far ,this is probably due to the CIPCLOSE=0 at the end of the served page, but if that's removed the browser locks up .
I know approx. nothing about http-html and it may stay that way for sanity reasons