Specifies the track format characteristics for the single-disk cartridge (top loaded) to be used for data interchange (see ISO 3562). The 7-bit coded character set specified in ISO 646 has been adopted, though, by agreement between the interchange parties, the 7-bit or 8-bit code extensions specified in ISO 2022 may be used. However, it should be noted that in this International Standard plain binary numbers in 8-bit bytes are used in the control field to define the control information.