There are many "classic" CW keyboards from the 70's, or even late 1960's, where the matching between pushbutton and CW symbol is simple one-to-one.
These predated widely-available computer keyboards so hams often made their own keyboards by drilling one hole for each key and putting a pushbutton in the hole. Generally there is no microcomputer inside, some of the oldest (1960's) didn't even have integrated circuits inside.
See here for some pictures from 40 or more years ago: http://qrqcwnet.ning.com/forum/topics/cw-keyboards-from-the-days-of-yore
You will see these showing up at hamfests etc. every so often.