Information Systems - Recorded Magnetic Tape Cartridge for Information Interchange - 4-Track@ Serial@ 0.250 Inch (6.30 mm)@ 6400 bpi (252 bpmm)@ Inverted Modified Frequency Modulation Encoded
This American National Standard is intended to provide a format and recording standard for a 0.250-inch (6.30-mm) wide@ 4-track magnetic tape in a cartridge to be used for information interchange between information processing systems@ communication systems@ and associated equipment utilizing a standard code for information interchange@ as agreed upon by the interchange parties. This standard refers solely to recording on the 0.250-inch (6.30-mm) magnetic tape cartridge and complements American National Standard for Information Systems - Unrecorded Magnetic Tape Cartridge for Information Interchange - 0.250 inch (6.30 mm)@ 6400-10000 ftpi (252-394 ftpmm) Phase Encoded@ ANSI X3.127.?? In that related standard@ the following sections are dealt with in detail: general requirements@ definition@ tape and cartridge@ physical and magnetic requirements@ speed requirements@ and write enable feature. Compliance with ANSI X3.127 is a requirement for information interchange. Data labeling and file structure should conform to American National Standard for Information Processing - Magnetic Tape Cassette and Cartridge Labeling and File Structure for Information Interchange@ ANSI/ IS0 4341-1978@ in order to provide for full data interchange between data processing systems CAUTION NOTICE: The user??s attention is called to the possibility that compliance with this standard may require use of an invention covered by patent rights By publication of this standard@ no position is taken with respect to the validity of this claim or of any patent rights in communication therewith The patent holder has@ however@ filed a statement of willingness to grant a license under these rights on reasonable and nondiscriminatory terms and conditions to applicants desiring to obtain such a license. Details may be obtained from the publisher. No representation or warranty is made or implied that this is the only license that may be required to avoid infringement in the use of this standard Purpose This standard defines the requirements and supporting test methods necessary to ensure interchange at acceptable performance levels. It is distinct from a specification in that it delineates a minimum of restrictions consistent with compatibility interchange transactions. The performance levels contained in this standard represent the minimum acceptable levels of performance for interchange purposes. They therefore represent the performance levels that the interchanged items should meet or surpass during their useful life and thus define end-of-life criteria for interchange purposes. The performance levels in this standard are not intended to be employed as substitutes for purchase specifications. Wherever feasible@ quantitative performance levels that shall be met or exceeded in order to comply with this standard are given. In all cases@ including those in which quantitative limits for requirements falling within the scope of this standard are not stated but are left to agreement between interchange parties@ standard test methods and measurement procedures shall be used to determine such quantities. U.S. Engineering Units are the original dimensions in this standard. Conversions of toler-anced dimensions from customary U.S. Engineering Units (similar to British Imperial Units) to SI units have been done in this standard in accordance with Method A as described in American National Standard Metric Practice@ ANSI/IEEE 268-1982@ and as described in International Standard for Toleranced Dimensions - Conversion from Inches into Millimetres and Vice-Versa@ IS0 370-1975. Method A should be used for economy unless a requirement for absolute assurance of a fit justifies use of Method B. In the national standards of ISO member nations@ additional rounding may be done to produce ??preferred?? values. These values should lie within or close to the original tolerance ranges Except as indicated in 1.2.3@ interchange parties complying with the applicable standards should be able to achieve compatibility without need for additional exchange of technical information.