| 摘要 |
PURPOSE:To obtain a magnetic bubble storing device having higher reliability, by using plural minor loops for index marker and performing rewriting of marker information. CONSTITUTION:A minor loop is composed of n loops x m bits and the n loops are composed of three marker information and n-3 data, and they correspond to the loops 0-2 and n-1 of a figure, respectively. Furthermore, one page is constituted of n bits and there are m pages, from Page 0 to Page m-1. In the figure, minor loops for marker information (Loop 0 to Loop 2) in a normal condition hold the following values: Page 0=all ''1'', and Page 1-m-1 = all ''0''. That is to say, when all the three marker information bits are ''1'', the subsequent accessing control is performed as the address starting point (Address 0) of the whole minor loops. Rewriting of the marker information is performed by checking the marker information periodically and immediately after the power supply of the magnetic bubble storing device is turned on, and by correcting the marker information when an abnormal condition occurs. |
