.Page ;++ ; FR3TO1 will take three bytes and create one composite byte from them. ; ; Input register usage: ; A := >CCCCCCCC< ; X := >BBBBBBBB< ; Y := >AAAAAAAA< ; ; Output register usage: ; A := >00AABBCC< == Nibblized ;-- FR3TO1 .Equ * ; From three to one routine Lsr A ; Ignore low six bits of "A" as they Lsa A ; will get shifted out and lost Sta Temp1 ; >00CCxxxx< Txa And #0C0 ; Clear low bits Ora Temp1 ; >BBCCxxxx< Lsr A Lsr A Sta Temp1 ; >00BBCCxx< Tya And #0C0 ; Clear low bits Ora Temp! ; >AABBCCxx< Lsr A Lsr A ; >00AABBCC< Tax Lda Nibl,X ; Nibblize the new composite byte Rts