I don't know anything about chess programming. If the columns in the array have specific meanings (e.g. the queen is always in column 4 or something similar) then it may make the code easier to follow if you give the index numbers a name. For example
byte queenCol = 4;
and then you could refer to it like this
if (array[queenCol] == 0) { ....
Sorry if the specifics are stupid but I hope it illustrates my point.
...R