AVR-Chat

At 09:01 PM 6/18/2004 -0700, Dave Hylands wrote:

>I think that the fastest way is to have a sixteen entry lookup table,
>where the answer is precomputed and stored.
>
>You could also store a 16 bit value, where each bit position holds the
>answer and use something like (in C):
>
>Lookup & ( 1 << val )

Yes, that was my first take.

In avr assembler:

clr     TEMP2
ldi     ZL,low(Xor_Table*2)
ldi     ZH,high(Xor_Table*2)
add     ZL,XOR_Dat
adc     ZH,TEMP2
lpm

I suppose this isn't all that ugly. 
What's this anyway, two PIC instructions worth?

I just get the feeling there's a better way.