SUB - Subtract Memory from Accumulator ;flags(N,Z,C)
SUB #opr ;A <= A - opr ;(IMM) 8 bit immediate
SUB opr ;A <= A - (opr) ;(DIR) 8 bit direct
SUB opr ;A <= A - (opr) ;(EXT) 16 bit extended
SUB ,X ;A <= A - (X) ;(IX) indexed no offset
SUB opr,X ;A <= A - (opr+X) ;(IX1) indexed w/8 bit offset
SUB opr,X ;A <= A - (opr+X) ;(IX2) indexed w/16 bit offset