IS 12876-1989

标准号：IS 12876-1989
发布日期：1990/7/1 12:00:00
实施日期：1999/12/31 12:00:00
适用范围：This International Standard specifies the Characteristics of a 3,81 mm (0.150 in) magnetic tape cassette to provide data interchange and physical interchangeability between information processing systems utilizing the ISO 7-bit coded character set (see ISO 646) and, where required, its extensions (see ISO 2022). The cassette is of the twin hub coplanar type, loaded with a 3,81 mm (0.150 in) wide magnetic tape for digital recording using the 31,5 bits per mm (800 bpi) phase encoding method. The direction of magnetization is in the longitudinal direction of the tape.NOTES1 Numeric values in the SI and/or Imperial measurement system in this International Standard may have been rounded, and are therefore consistent with, but not exactly equal to each other. Either system may be used, but the two should be neither intermixed nor converted. The original design was made using the metric measurement system.2 Throughout the remainder of this International Standard for the sake of simplicity the recording density is stated as 32 bpmm (800 bpi) nominal.This International Standard applies to cassettes and data used for interchange. Where it applies for testing only, this is specifically stated.