; ( n1 -- n2 ) Arithmetics
; R( -- )
; logarithm base 2 or highest set bitnumber
VE_LOG2:
.db $04, "log2",0
.dw VE_HEAD
.set VE_HEAD = VE_LOG2
XT_LOG2:
.dw PFA_LOG2
PFA_LOG2:
movw zl, tosl
clr tosh
ldi temp0, 16
mov tosl, temp0
PFA_LOG2_1:
dec tosl
brmi PFA_LOG2_2 ; wrong data
lsl zl
rol zh
brcc PFA_LOG2_1
rjmp DO_NEXT
PFA_LOG2_2:
dec tosh
rjmp DO_NEXT