The LuX Industry LX910C works by turning "segments" on or off relatively to the input value on either the c0 or c1 pins (it does not matter which).

A positive value turns on the segment at the index corresponding to the value of the input; and a negative value turns off the segment at the index corresponding to the absolute value[en.wikipedia.org] of the input.

However, the input values 999 and -999 are special values, as in they turn the all the segments on or off (respectively). In addition, the input value 0 has no meaning, and is ignored.

Thus, the meaningful input values are [1, 998] (and, by extension, [-998, -1]).

The dimensions of the screen are 320 pixels per 405 pixels. However, in order to be considered as a separate "segment", different black shapes have to be separated with white pixels. As a consequence, the maximum number of segments, vertically, is 202, and horizontally, 160.

The way to determine how many segments should be used for this matrix is by determining the highest number less than, or equal to, 998, that factors to terms lower than, or equal to 202.

Now, 998 does not factor much. It factors in 2 * 499, which isn't less than 202 to begin with. 997 is a prime number. Nothing to see here.

The first number we can properly factor is 996. However, it does not factor in very usable terms: 12 x 83: 12 would make the segments 25 px wide (with 5 and 4 px margin), but 3 px high (with 37 px margins). The corresponding matrix is available below, in case you want to use it.

With 995, the factorization gives 5 x 199, which isn't really usable. There is a matrix below with the fitting dimensions, but I won't go into details here.

The second number we can properly factor is 994. It can be factored as 14 x 71. This is essentially the same as the previous matrix, with a slight variation: the segments are 21 px wide (with 7 and 6 px margin), and 4 px high (with 25 and 26 px margin).

993 factors in 3 x 331, and that will not even yield a usable pattern.

The last number we can properly factor is 992. This is the last one, because it is the highest number (below 999) that can yield a proper matrix. 992 factors as 31 x 32. This is great, as the number of divisions in both directions is almost equal. It leads to segments being 9 px wide (with 6 and 5 px margin), and 11 px high (with 11 px margin).

Note: In addition to the matrices listed above, I made a 998 matrix (the maximum possible) using a 999 pattern (27 x 37, 10 px wide, 12 px margin, 10 px high, -1 px margin). It is kind of a hack in the fact that a square is missing, and that an entire line of pixels was removed from the bottom line in order to make it fit (they are 9 px in height).