JPS598902B2 - Magnetic bubble storage method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a magnetic bubble storage method for dealing with a case where a minor loop is defective in a magnetic bubble storage device having a major loop and a minor loop.

Generally, in magnetic bubble storage devices, the bubble
Defects often occur in memory chips at several locations.

If such a defect exists in the major loop, for example, there is no specification and such a bubble memory chip would be considered a defective product, but if the defect exists in the minor loop, then there is no specification. are often used with some kind of countermeasure. Conventionally, as a countermeasure for such cases, it is necessary to connect PRO externally to correspond to the bubble memory chip.
M(Program-mableReadOnlyMem
ory), write information about the location of the defect there, and read it in the bubble memory.
When writing, referring to the information written in the PROM, it is possible to avoid defective minors.
A method is adopted that does not use loops.

However, if this method is used, the PROM must be arranged in correspondence with each bubble memory chip, which increases the number of parts and complicates the configuration.

The present invention enables operation without using a defective minor loop without placing an external PROM, and makes it possible to utilize a bubble memory chip having a defective minor loop with an extremely simple configuration. This will be described below in detail with reference to embodiments.

The figure is an explanatory diagram of main parts of a magnetic bubble storage device implementing the present invention.

In the figure, LG is the major loop, LM is the minor loop from l to n, WR is the writer, and ER
is an eraser, Dv is a divider, DT is a detector, TG is a transfer gate, and FL is a defect.

The operation of a normal magnetic bubble storage device is as follows.

First, information is sent from the writer WR to the major loop LG.
That is, when a magnetic bubble is written, the bubble is sequentially transferred through the major loop LG, and when it reaches a predetermined position, is transferred to the minor loop LM by the action of the transfer gate TG. The bubbles transferred to the minor loop LM are transferred and stored therein, and are returned to the minor loop LG as needed and read out by the detector DT. The eraser ER erases old information before writing new information. Now, in the present invention, at least one defective rube writing mark loop is set in the minor one loop LM.

In the figure, it is assumed that the first minor loop LM is the one. It is assumed that loop 1 for this defective loop writing mark is defect-free and is common to all chips. This loop is used to write information indicating the position where information indicating the presence or absence of a defect is written in each minor loop, that is, a bubble, and is used for writing other general information. In the illustrated example, for example, the fourth minor loop LM is a defect F that prevents the transfer of the bubble or eliminates it.
I have L.

Therefore, information indicating the location of defect information, that is, a defect information position display mark, is written in the l-th minor-1 loop LM, and for the second and subsequent minor-1 loop LM, the first minor-1 loop LM is written.・At the location corresponding to the location where the defect information position display mark is written on the loop LM,
Information indicating the presence of bubbles is written to the loop with no bubbles and no defects with respect to the minor loop, and the location of the defect information in each minor loop is stored on the minor loop LM. In the figure, the defect information position display mark written in the l-th minor-1 loop LM is represented by a black circle, and the defect-free loop information (with bubbles) written in the defect-free minor-1 loop is also a black circle. It is expressed as Note that white circles indicate normal information. In a device in such a state, when the transfer gates TG are opened all at once, information is transferred from the minor 1 loop LM to the media 1 loop LG in parallel, and the information is transferred from the minor 1 loop LM to the media 1 loop LG. When the information is transferred and reaches the detector DT, it is read out serially. First, a defect information position display mark comes out from the l-th minor loop LM, so
It can be seen that the information read out in succession indicates whether the loop is defect-free or defective.

In this case, information, that is, bubbles come out from the second and third minor-loop LM, so they can be used.
Since no bubbles come out of loop LM, it can be determined that it is unusable. Note that the defect information in each minor-1 loop LM does not necessarily need to be written in a position similar to the defect information position display mark of the first minor-1 loop LM, but if it is written in a similar position, each transfer This is extremely advantageous because the position indicating mark and the defect information are read out in succession by a single operation of the gate as described above. By the way, in order to perform the above operation, it is clear that it is preferable that the bubble, which is the defect information position display mark, be detected as quickly as possible when the device is turned on and a rotating magnetic field is applied. , there are some conditions to do so.

That is, a) defective loop for writing the defect information position indication mark, that is, the lth minor loop such as the lth minor loop LM in the illustrated example is located at the location closest to the detector D. (1) When starting and stopping a bubble, it is necessary to ensure that the location where defect information is written is always the same. (3) When starting and stopping a bubble, it is necessary to make sure that the defect information is always written in the same location. It is necessary to stop it at a position closest to the detector D, so that the bubble, which is an information position indicator mark, can be read out. Incidentally, the execution of steps (a) and (c) above can be easily controlled by digitally using a counter. As can be seen from the above description, according to the present invention, in a magnetic bubble storage device having a major one loop and a minor one loop, at least one minor one loop is a defective loop as a write mark loop. An information position indication mark is written, and in the other minor loops, a non-defective minor one is written at a location corresponding to the location where the defect information position indication mark is written in the defective lube writing mark loop. Write the information for the loop with bubbles and the defective minor 1 and loop without bubbles to memorize the location of the defective minor 1 and loop on the minor 1 and loop, and perform normal information processing. At this time, after reading the defect information position display mark,
Based on the presence or absence of bubbles that are read out in succession, the non-defective minor-1 loop and the defective minor-1 loop are determined and their use or non-use is determined.
To utilize a magnetic bubble storage device having a defective negative lube, in which defect information can be easily obtained even after the power is turned off and turned on again, without having to adopt a complicated configuration such as installing a I can do it.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram of a main part of an apparatus implementing an example of the present invention. In the figure, LG is a medial loop, LM is a minor loop, WR is a writer, an ER eraser, a D divider, a DT detector, TG is a transfer gate, and FL is a defect detector. Each is shown below.

Claims (1)

[Claims] 1. In a magnetic bubble storage method using a magnetic bubble storage device having a major loop and a minor loop, at least one minor loop is used as a defective loop writing mark loop to write information indicating the position of defect information. In other minor loops, in the defect-free minor loop, there is a bubble and In the case of a defective minor loop, information without bubbles is written, and during normal information processing, the position display information is read out, and depending on the presence or absence of bubbles in the subsequently read information. Defect-free minor loop and defect-free minor loop
A magnetic bubble storage method that distinguishes between loops and determines whether to use them or not.