User files are placed in the data area.
∙ One file is not necessarily arranged consecutively, but generally interleaved. Mode2 sector is a mix of Form1 and Form2, but the file size is converted to 2048 bytes.
For convenience, Mode1 sectors are formally treated as Form1 sectors with a subheader of 0.
∙ Form2 sector data must be 2324 bytes, and fractional bytes are not allowed.