'`' 0x0630
and that is indeed right and exactly what you are saying .. the ( ` ) - which in most cases is over theTAB in the left of the ( 1) .. there lies the 0x0630 , and that is the THAL in case you don't have access to a Unicode table ..
you want to make the key <BKSL> for the 'thal' or ` don't u ? even if you compared that with this table the table says : '\' 0x005C ----------> that's <BKSL> key '`' 0x0630 -----------> that's <TLDE> key