HONK! i think i got it.

Let's say B1=%11110000

R0 should be Bit 0 of B1, R7 should be Bit7 of B1... i'm i right?
If so...
R0=B1.0
R1=B1.1
R2=B1.2
R3=B1.3
..
...
R7=B1.7