This is a common requirement. We've created several such systems for custom designs. As a result we've created a set of include files and routines which can be used to create and manage menus with keypad input. We're planning to make this a product in fall of 1999. Because there are so many ways to do this, and so many different kinds of input possible, it's hard to create a universal solution. We don't claim to have done so. We also would hesitate to call our menu code 'easy to use'. It requires some study and understanding of the 20 or so routines and how they interact. This would be a great application for an object-oriented wizard plug-in for RAD51, and in fact we intend to do that.
We will create a set of open-source classes and examples for use with TINI Java 1.0 or later.
There is an example in the DPB2 examples file which shows one way of scrolling text across one line of a multi-line LCD.
When used with our enclosure and keypads, the 20x4 LCD lines up over the top row of keys. You can use the bottom line of the LCD as a row of soft prompts. You get 4 groups of 5 characters for each of the four keys. This means each prompt can be 3-4 characters with a space or two between them.