Defines the download bit image of the number of dots specified by X and Y. X
specifies the number of bytes in the horizontal direction.
Y specifies the number of bytes in the vertical direction.
Horizontal direction dot count is X x 8 dots; Vertical direction dot count is Y x
8 dots
d indicates the bit-image data. Bits that correspond to the dots to print are 1,
and the bits that correspond to the dots that are not printed are 0.