>For example if you have: > tst.w d0 > seq variable > (...) > >variable dc.b 0 > >It means: "if d0.w=0, variable = $FF, else variable = $00" *tst* is the instruction test for NEGATIVE OR ZERO. *tst.w d0* means *If d0.w <= 0, variable = $FF, else variable=$00*