AVR-Chat

>
>Solution 1
>
>Cross wire port A to Port B (or any other port combination. Output byte
>on one port and read back on another.

I like it!  :)

Interestingly enough, it's not THAT much faster than the table, but 
down here it counts.

I'm pretty sure this table is right.

reverse:    ; 0   1   2   3   4   5   6   7   8   9   A   B   C   D   E   F
                 .db 
$00,$80,$40,$C0,$20,$A0,$60,$E0,$10,$90,$50,$D0,$30,$B0,$70,$F0 ;$0X
                 .db 
$08,$88,$48,$C8,$28,$A8,$68,$E8,$18,$98,$58,$D8,$38,$B8,$78,$F8 ;$1X
                 .db 
$04,$84,$44,$C4,$24,$A4,$64,$E4,$14,$94,$54,$D4,$34,$B4,$74,$F4 ;$2X
                 .db 
$0C,$8C,$4C,$CC,$2C,$AC,$6C,$EC,$1C,$9C,$5C,$DC,$3C,$BC,$7C,$FC ;$3X
                 .db 
$02,$82,$42,$C2,$22,$A2,$62,$E2,$12,$92,$52,$D2,$32,$B2,$72,$F2 ;$4X
                 .db 
$0A,$8A,$4A,$CA,$2A,$AA,$6A,$EA,$1A,$9A,$5A,$DA,$3A,$BA,$7A,$FA ;$5X
                 .db 
$06,$86,$46,$C6,$26,$A6,$66,$E6,$16,$96,$56,$D6,$36,$B6,$76,$F6 ;$6X
                 .db 
$0E,$8E,$4E,$CE,$2E,$AE,$6E,$EE,$1E,$9E,$5E,$DE,$3E,$BE,$7E,$FE ;$7X
                 .db 
$01,$81,$41,$C1,$21,$A1,$61,$E1,$11,$91,$51,$D1,$31,$B1,$71,$F1 ;$8X
                 .db 
$09,$89,$49,$C9,$29,$A9,$69,$E9,$19,$99,$59,$D9,$39,$B9,$79,$F9 ;$9X
                 .db 
$05,$85,$45,$C5,$25,$A5,$65,$E5,$15,$95,$55,$D5,$35,$B5,$75,$F5 ;$AX
                 .db 
$0D,$8D,$4D,$CD,$2D,$AD,$6D,$ED,$1D,$9D,$5D,$DD,$3D,$BD,$7D,$FD ;$BX
                 .db 
$03,$83,$43,$C3,$23,$A3,$63,$E3,$13,$93,$53,$D3,$33,$B3,$73,$F3 ;$CX
                 .db 
$0B,$8B,$4B,$CB,$2B,$AB,$6B,$EB,$1B,$9B,$5B,$DB,$3B,$BB,$7B,$FB ;$DX
                 .db 
$07,$87,$47,$C7,$27,$A7,$67,$E7,$17,$97,$57,$D7,$37,$B7,$77,$F7 ;$EX
                 .db 
$0F,$8F,$4F,$CF,$2F,$AF,$6F,$EF,$1F,$9F,$5F,$DF,$3F,$BF,$7F,$FF ;$FX