"OUT OF STACK SPACE" when working with Function Keys (F1,F2...) 1

[aliinal]

I've written a program that uses function keys to get input from user. Ex F1 to go to add section F2 to delete etc.etc.
For this i used the commands below

KEY(X) ON 'Where x is the Function Key's keyboard scan code
ON KEY(X) GOSUB aaaaa

but in runtime if i hold that function key pressed or hit several times i get the error "OUT OF STACK SPACE"...
It's an interesting error for this program cus no recursive subs...
Thanks for your help

 

[MiggyD]

suggestion: in that "gosub aaaa" use the KEY OFF command so that if the KEY IS still pressed WHILE in that sub routine, it doesn't call itself again.

I'm pretty certain it's called a "recursive call", you may have heard of it.

THEN, just before the RETURN statement use the KEY ON command to reactivate the key's usability.

Good Luck.
--MiggyD "The world shrinks more and more with every new user online."

 

[MiggyD]

Glad to have helped.
--MiggyD "The world shrinks more and more with every new user online."

 

[logiclrd]

Actually, MiggyD, this is called a re-entrant call. The routine did not call itself, but it was called while it was still running. This is one possibility, especially if the routine inside the key handler takes a long time to execute.

The other possibility is that aliinal's program isn't '[tt]RETURN[/tt]'ing from the handler, but instead explicitly '[tt]GOTO[/tt]'ing the top of some loop. In this case, the stack would still have the return value from the keyboard handler '[tt]GOSUB[/tt]' call. Invoking the handler repeatedly would slowly consume all of the available stack space, eventually causing the program to crash.