JPS597156B2 - 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
It often happens that memory chips have several defects.

If such a defect exists in the major loop, there is no specification at all, 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. It is often used with some kind of countermeasure. Conventionally, as a countermeasure for such cases, it has been made compatible with bubble memory chips and publicized externally.
OM(ProgrammableReadOnlyM
memory) and write information about the location of the defect there, and when reading and writing in the bubble memory, the information written in the PROM is referred to. A method is adopted in which defective minor loops are not used.

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 the use of defective minor loops without placing an external PROM,
It enables the use of bubble memory chips with defective minor loops with an extremely simple configuration.
This will be explained in detail below 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 number 1 to n, WR is the writer, and ER
is an eraser, Dv is a divider, DT is a detector, T6 is a transfer gate, and FL is a defect.

Typically, the operation of a magnetic bubble storage device is as follows.

First, information is sent from the writer WR to the measurer loop L6.
That is, when a magnetic bubble is written, the bubble is sequentially transferred through the major loop L6, and when it reaches a predetermined position, it is transferred to the minor loop LM by the action of the transfer gate T6. The bubbles transferred to the minor loop LM are transferred and stored therein, and are returned to the major loop L6 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 loop 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. This defective loop writing mark loop is selected to be defect-free and common to all chips. Then, in this loop, information indicating the position where information indicating the presence or absence of a defect is written in each minor loop is written, that is, a bubble, and it is not used for writing other general information. . In the illustrated example, for example, the fourth minor loop LM is a defective FL that prevents or eliminates bubble transfer.
have.

Therefore, information indicating the location of the defect information, that is, a defect information position display mark, is written in the first minor one loop LM, and for the second and subsequent minor one loop LMs, the first minor one loop LM is written.・At the location corresponding to the location where the defect information position display mark is written on the loop LM,
Write the information that there is no bubble in the loop, and write the information that there is a bubble in the defect-free minor-1 loop, and write the information that there is a bubble in the minor-1 loop.
The location of defect information within each minor loop is stored on the top. In the figure, the first minor loop LM
The defect-free loop information written in the defect-free minor 1 loop is represented by a black circle.
(with bubble) is also represented by a black circle. Note that white circles indicate normal information. In the device in such a state, by opening the transfer gates T6 all at once, information is transferred in parallel from the minor 1 loop LM to the major 1 loop L6, and the information is transferred in parallel from the minor 1 loop LM to the major 1 loop L6. When the information is transferred to the detector DT, it is read out serially. First, a defect information position display mark appears from the first minor loop LM, and then It can be seen that the information read out indicates whether the loop is defect-free or defective.

In this case, information, that is, bubbles, come out from the second and third minor one-loop LMs, so it is okay to use them, and from the fourth minor one-loop LM. Since no bubbles appear in , it can be determined that it is unusable. Note that the defect information within each minor loop does not necessarily refer to the first minor loop.
It is not necessary to write in a position similar to the defect information position indication mark of the loop LM, but if it is written in a similar position, the position indication mark and defect information will be changed as described above by one action of each transfer game +. This is extremely convenient since they are read out in succession. 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) Defect loop for writing the defect information position indication mark The write master loop, ie, the first minor loop LM in the illustrated example, is placed at the location closest to the detector DT. When starting/stopping a bubble, it is necessary to ensure that the location where the defect information is written is always the same.
It is necessary to start the bubble and stop it at the position closest to the detector DT so that the bubble, which is the defect information position indicator mark, can be read out first. Incidentally, the execution of the above steps) and d) can be easily controlled by digitally using a counter. As is clear from the above, in the present invention, at least one of the loops having no defect among the minor loops is set as a loop for defective loop writing mark, and defect information is written in any one bit of the loop. Write information indicating the location and other minor points.
In the loop, write information with a bubble in a non-defective loop and without a bubble in a defective loop at a location corresponding to the location where the defect information position display mark is written in the loop for defective loop writing marks. By using these marks and information, it is possible to purge defective minors and loops without requiring a large number of external PROMs. The information regarding the defective loop read out by the device D is processed and stored in an external circuit, and during normal data processing of the magnetic bubble storage device, the stored information regarding the defective loop is read out and constantly compared with the information regarding the defective loop. Bubble memory chips must be used except for Therefore, in this case, the configuration of an external circuit such as a storage section provided externally becomes a problem. That is, such an external circuit must also be configured as simply as possible, but the present invention can meet such requirements. In the apparatus shown in FIG. 1, if there are 128 minor-1 loops LM, information regarding the defective loops will be read out in the form of a 128-bit signal.

However, if this is used as it is, the amount of data to be handled will be enormous, so in the present invention, this is converted into binary numbers and handled. That is, if you do that, 1
It is now possible to perform processing such as address storage on a 28-bit signal using a 7- to 8-bit configuration; an 8-bit configuration requires 1 byte, so if there are 2 defective loops, 2 bytes are required.
If there are 3 bytes, it is sufficient to configure it with 3 bytes, and to make it milky, a defective address conversion unit is required.
FIG. 2 is a block diagram showing an example of an apparatus for implementing the present invention, in which BO is a magnetic bubble memory chip as explained in connection with FIG. 1, DT is a detector, Cv is a defective address converter, and ME is a Each shows a defective address storage section.

Since the problem here is the defective address translation unit Cv, this will be specifically shown in FIG. 3 and explained.

That is, the defective address conversion unit Cv is roughly divided into a 2X counter CUl (first counter) and a 2y counter C. , (second
counter). FIG. 4 is a timing chart representing signals at key points in the system seen in FIGS. 1-3. Now, magnetic bubble memory chip B.

When information regarding the defective loop is read from the detector DT via the detector DT, an information signal as shown in FIG. 4 is obtained at point a in FIGS. 2 and 3. The shaded pulses are defect information position indication marks read from the first minor loop in FIG. Based on this defect information position display mark, the counter start signal is sent to the counter CU.
Add to l and start. In the minor one loop LM shown in FIG. 1, the fourth loop is defective, so the defective loop information signal is zero because the fourth loop is missing. Therefore, based on this, a write command signal is input into the storage unit ME, and the output of the counter CUl at that time, for example...
The information indicating that the address of the defective loop is number 4, such as 00000100, is stored in the storage unit ME.
By the way, if there are a plurality of defective loops, the above-described operation is performed again and the address of each defective loop is stored in the storage section M.

Therefore, it is necessary to scan the memory section ME in the y direction for addressing, and for this purpose, a counter CU2 is provided. That is, counter CU2
The address of the defective loop is in the memory section M. Each time the address of the defective loop is written, the write command signal is simultaneously applied to shift the address of the defective loop to address the location in the memory ME to be written next. In the illustrated counter CU2, three lines are stored in the memory section ME, so normally eight defective loops can be dealt with. 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 used as a defective loop writing mark loop. Write information location display mark,
In other minor loops, there is a bubble in the non-defective loop at a location corresponding to the location where the defect information position display mark is written in the defective loop write mark loop.
In addition, each defective loop is written with bubble-free information, and the information regarding the defective loop from all the negative loops is stored externally by converting only the address of the defective loop into a binary number. When performing normal information processing in the magnetic bubble storage device, the address of the defective loop stored in the storage section is read out and constantly checked against the defective loop. It is possible to prevent the use of PROMs, and there is no need to install a large number of external PROMs like in the past. can be easily obtained, and the purpose can be achieved with an extremely simple external circuit configuration.

[Brief explanation of the drawing]

Fig. 1 is an explanatory diagram of main parts showing an example of an apparatus for carrying out the present invention, Fig. 2 is a block diagram showing an example of an apparatus for carrying out the invention, and Fig. 3 is a defect address in the apparatus shown in Fig. 2. FIG. 4 is a main part block diagram for explaining the operation of the conversion section, and a signal timing chart for explaining the operation. In the figure, L6 is the major loop, LM is the minor loop, WR is the writer, ER is the eraser, Dv is the divider, DT is the detector, T6 is the transfer gate, and FL
is a defect, Cv is a defective address translation section, and ME is a defective address storage section.

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, there is a bubble and a defect in a defect-free minor loop at a location in a predetermined relationship with the location where the position display information is written in the defective loop writing mark loop. For minor loops, after writing information without bubbles, information about the defective loop is detected from all minor loops, and from that information only the address of the defective minor loop is sent to the defective address converter. When converting it into a binary number and storing it in a defective address storage unit, and performing normal information processing in the magnetic bubble storage device, the address of the defective minor loop is read out from the defective address storage unit and collated, and the defective minor loop is stored in the defective address storage unit. - A magnetic bubble storage method characterized in that the information processing proceeds without using a loop.