Let that mouse sort out those shifty characters!

Do you remember those childhood toys which comprised a square frame enclosing 15 or more letters that you slid around to arrange into different orders? Perhaps even your children have one now. In their day they were the forerunners of Rubic’s Cube, before both became ousted by PlayStation and the like.

Recently, the author was considering how best to illustrate in a simple fashion the way in which a PC’s mouse could be put to alternative good use with a PIC, following on from his article PIC to PS/2 Mouse and Keyboard Interfacing (Aug ’04). Somehow, these letter frames came to mind, and sparked off a series of highspeed bashings at the keyboard to write the code for a modern equivalent.

The result of just a few hours coding and programming is this AlphaMouse Game, in which a 2-line 16-characters (per line) alphanumeric liquid crystal display (l.c.d.) replaces the lettered frame, and a PC’s PS/2 mouse controls the movements of 31 letters around the 32-position area.

Unable to resist addiction again, the author has inevitably used a PIC microcontroller to do the hard work, interpreting your leisurely efforts at moving and clicking the mouse as the whim takes you. And unlike the original frame game, you’ve been provided with the full 26-letter alphabet, plus a handful of symbols to arrange into what ever order takes your fancy. There is a randomiser which selects the letters presented and in what order prior to each game. The variety is practically infinite, and you are probably as likely to get repeats of letters scattered around as you are to get just one of each. Should you find some games looking harder than others, you may even activate the randomiser again if you don’t like the offering!

You can also deliberately select games in which four spaces instead of one are provided, into which the letters can be shunted while sorting the others. Even the author, not normally one for much gameplaying, found himself getting hooked on the game’s fascination – and the way in which it is sometimes necessary to “trap” a letter using others, in order to make it go into the space you want. A bit like persuading sheep to go into their pen without a sheepdog!