Matrix user forums

Hello,
That seems too crazy ... I must make a silly mistake! But ...

li is a byte

li = 255 MOD 4 show in variables window 3 ... that's OK

li=0
li = (li-1) MOD 4 show 255 ???

li = (li-1) AND 0b00000011 do the job fine of course.

Some ideas?
Best regards.