Only ON KEY(15) to ON KEY(20) are working, ON KEY(21) through ON KEY(25) no response

[voidstar78]

Wanted to exercise ON KEY for a little piano sample. But using ON KEY, I can only get 6 keys registered. Not sure if this is an internal limit, or if there is some issue with ON KEY(21) to ON KEY(25). Manual said index 15..25 should be user defined, unless I misread it?

[voidstar78]

I see at http://www.antonis.de/qbebooks/gwbasman/ it says only index 15 to 20 are available, so maybe PC-BASIC technically only supports that to be more compatible? Or is there some other way to enable the 21-25 index?