That's similar to how the scandinavian ao/aa, ae and oe became single letters: å, æ and ø and eventually in Swedish: å, ä and ö where the umlauts originally where small "e"s written above an a and o respectivly (the å still has a small "o" above it).
Great Hierophant wrote:
While the AVS has some non-standard key assignments, I assume this was done to require as few changes to the Family BASIC software as possible. I would note the unusual inclusion of £ and ¥, which suggests something of an international flavor to the keyboard. I think the ¥ may have a function in Family BASIC.
Was there even a standard key assignment during this time? It seems to me every computer had their own key assignment. And the IBM PC wasn't the definitive PC it is today.
I don't think the ¥-symbol was used in Family BASIC if I remember correctly (I did do a fair bit of the Family BASIC manual translation and also translated most of the V3 manual after all). The flavor of BASIC in Famibe is based on Sharp and Hudson's Hu-BASIC, which in turn is based on Microsoft's BASIC used in Commodore 64 I think. Therefore it uses the same syntax and most of the same commands as other BASIC languages. It's mostly only special commands for Famicom-specefic things like sprites and BG data in the CHR ROM, and the like, that has its own commands. The $-symbol is used though.
I believe the ¥ is there out of Japanese pride more than for any other reason. Especially since this was a prototype, it wasn't necessary make everything perfectebly suitable for an American audiance at once, there were still time to change any of the keys if the American publishers weren't happy with it.