AVR-Chat

first of all you need to define your HMI.
basically HMI is an interface to humen. so you need to
display things on a visualisation device such as
graphic or text LCD, or even a monitor.
then you need to get user choices, using keypad,
keyboard, mouse, etc.
after all you need to decide how to show internal data
to user and how response to user or host computer
system. the best way as i guess is to implement a
basic but customizable environment (hardware and
software) without any doubt about amount of data or
even program size. this could be done using some
logics like NanoVM java interpreter or something which
does not limit your work with microcontroller
limitations.

good luck;
reza

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