>Carlos,
>
>The MAKELPARAM macro merges two WORDs (16 bits each) in one DWORD (32 bit). This is OS syntax:
>

>LPARAM MAKELPARAM(
>    WORD wLow,
>    WORD wHigh
>);
>

>And a equivalent VFP function:
>

>FUNCTION MakeLParam(nLo, nHi)
>RETURN m.nLo + m.nHi * 0x10000
>

>Note that neither nLo nor nHi should exceed 0xffff, since they are WORDs.

That worked, thank you Anatoliy