EVAL doesn't work in old program

[adrunodro]

Hi!
I'm trying to use some programs I wrote on the pass but the don't work with the the firmware I use nowadays.
The stops on the function eval

This is an example:

EXPORT YO()
BEGIN
LOCAL k,f;
INPUT({{f,[8]},A,B,H,S},"Data Input",
{"dy/dx=","x0=","y0=","Step=",
"# Steps="});
X:=A;
Y:=B;
PRINT("___________");
PRINT("Solución por Método Euler");
PRINT("");
FOR k FROM 1 TO S DO
PRINT("X="+X);
PRINT("Y="+Y);
Y:=(Y+H*EVAL(f));
PRINT("___________");
X:=(X+H);
END;
PRINT("X="+X);
PRINT("Y="+Y);
END;

Someone could tell me what changed?

Thanks