    0, 0,
        0, 1,
        1, 1,
        0, 0,
        1, 1,
        1, 0,

        // between top rung and middle
        0, 0,
        1, 1,
        0, 1,
        0, 0,
        1, 0,
        1, 1,

        // top of middle rung
        0, 0,
        1, 1,
        0, 1,
        0, 0,
        1, 0,
        1, 1,

        // right of middle rung
        0, 0,
        1, 1,
        0, 1,
        0, 0,
        1, 0,
        1, 1,

        // bottom of middle rung.
        0, 0,
        0, 1,
        1, 1,