Sioc and Offsett $0800 Autopilot Approach Hold

Hi All,
Hope someone can help with the code for this offset.
I can set it but another press of the switch and it wont reset.
Ive used the code for Nav Hdg and it works ok. I think it maybe
something to do with G/S hold, the two are linked somehow.
It beyond my logic to program this , here is my code bit.

Var 0001 \\ LCD display 1
Var 00015, Link FSUIPC_INOUT, Offset $0800, Length 4
{

IF V00015 = 1
{
V0001 = 4

}
Else
{

v0001 = 1

}

}

What im doing is recording when a button(Approach) via my bodnar board is pressed then activating a page on the LCD panel with text and data.

Thanks
Regards
Les

Solved:
It appears Approach activates G/S Hold and sets both. So I had to AND both Offsets to reset them so I can toggle
the AP Approach button.
Les