alternative trackspare track备用: reserve; spare; alternate; b ...磁道: magnetic track; track替用磁道: alternate track无用磁道寄存器: dtr dead track register备用: reserve; spare; alternate; backup; standby application; standby下载手机词典可随时随地查词查翻译关注微信公众号：chachacidian，回复:备用磁道，即可在微信中查询翻译
