DE2129378A1 - Method for operating a magnet wire storage system - Google Patents

Description

Method of operating a magnet wire storage device A magnet wire storage device is known to consist of magnet wire bit lines and word lines that form the cross the aforementioned magnet wire bit lines (see "Development reports from Siemens-Halske-Werke", Special issue September 1969 - Rapid memory -, page 3, pages 25 to 29 and page 49 to 56). The word lines each include a plurality of magnet wire bit lines.

One bit is stored at each point of creation. Becomes a word line suitably energized, the bit lines it encompasses the bits stored at the associated crossing points are output. When controlling The word lines can also interact with currents flowing through magnet wire bit lines information is entered. One bit is always on one Crossing point due to magnetization of the magnetically anisotropic surfaces of the associated magnet wire bit line in one or the other circular Direction saved.

During the operation of such a magnet wire store occurs unintentionally a deleterious effect, which is that by passing through the word lines sent word current pulses the circular magnetic preferential direction against the is rotated in the axial direction for the magnet wire bit lines. This twist can become so severe that reading or writing disorders occur (see ?? The Bell System Technical Journal ", Volume 47, October 1963, No. 8, Pages 1539-1541). This effect can be achieved through the choice of suitable material and through stabilization treatments of the magnet wires used. It but can not do this be completely ruled out that the disorders mentioned and that therefore initially saved information will be lost.

The invention now shows a way how this harmful effect can be completely can be avoided. For this purpose, the magnetic wire storage is used in a certain way operated. The invention accordingly relates to a method for operating a magnet wire store, that of magnet wire Eitleitung with a magnetic used as a storage layer anisotropic surface layer and word lines crossing these magnet wire bit lines is built up and in which one bit at each intersection by magnetization the surface layer stored in one or the other circular direction is and is read out with the help of a word stream pulse generated by the associated Word line is sent. This method is characterized in that in predetermined approximately equal time intervals the assignment of the two circular directions for the magnetization for the two binary values of a bit is changed and that the time intervals are at least so short that those within a time interval Word stream pulses sent over the word lines do not cause any read or write interference lead due to twisting of the preferred magnetic direction.

As for the operation of a magnet wire storage facility anyway -must be provided 'that the surface layer in one or the other Can magnetize circular direction, are for the inventive method only additional switchings are required for these facilities that are equipped with can be carried out with little effort. It has been shown that with the usual Utilization of magnetic wire storage, it is sufficient if the assignment at time intervals is changed, which are in the order of one or a few years. Of the normal Operation is therefore not affected by this change.

The following are the inventive method as well as examples for particularly suitable process steps explained in detail. aside from that is also shown as a per se known arrangement, which is attached to the magnet wire bit lines is to be connected for operation to carry out the method according to the invention can be designed. Only minor additions to this arrangement are required. All of this is explained with reference to the figures.

For this purpose, FIG. 1 shows how a magnet wire memory is constructed in principle is.

FIG. 2 shows a crossing point between a word line and a magnet wire bit line and, like there, the axial and circular directions the magnetization.

Figure 3 shows an example of an arrangement for performing the method according to the invention.

The magnet wire memory shown in Figure 1 has the word lines WL and the Niagnet wire bit lines L. At the intersection of these newspapers one bit is stored in each case. What this storage consists of is in the figure 2 to recognize. There are the two circular ones at the magnet wire bit line L. Directions zO and z1 are drawn in for positions of rest of the magnetization. It shows direction z1 clockwise and direction zO counterclockwise. If a bit is stored at the intersection shown, the magnetization shows in one or the other of the two circular directions shown for the magnetization. Such a rest position for the magnetization is there by caused the interaction of two magnetic fields or two currents. Through a the word current pulse flowing through the word line WS generates a magnetic field, by which the magnetization is rotated almost in the axial direction a. A relative low magnetic field that is a circular Has direction and with help a current pulse flowing through the magnet wire bit line L is caused, then determines in which circular direction the magnetization occurs in the next Shows rest position. This depends on the polarity of the current impulse that passes through the magnet wire bit line L is sent. All of these effects are based on the fact that the magnetic surface layer of the magnet wire bit line is magnetically anisotropic in such a way that the axial direction is the direction of heavy magnetization and the circular directions are the directions of easy magnetization. Pure that Reading is carried out with the aid of a word current pulse that flows through the word line WL, uses a magnetic field that is perpendicular to the direction of easier magnetization, ie to the axial direction and that the magnetization from the circular rest position unscrews in the axial direction. This creates a voltage pulse on the magnet wire bit line L induces its polarity from the circular direction of the rest position of the magnetization is dependent. The further in the rest position the magnetization is already out of the circular Direction is turned out, the smaller the induced voltage pulse is obviously.

Such an unscrewing or twisting can now result if a large number of forward current impulses have influenced the crossing point under consideration. The bit stored there may then have become illegible.

In the method according to the invention, an effect is now used, which enables such unscrewing or twisting to be reversed. This is because it is the binary value of the stored at the intersection point under consideration Bits changed, the result is a new rest position of the magnetization in which the Magnetization points exactly in the opposite direction. With the unscrewing resp. Rotation of the direction of magnetization during the previous one During operation, the directions of easier magnetization have also rotated. The magnetization in the rest position points in such a direction, either clockwise or counter-clockwise. One can now determine the new direction of magnetization, in which the magnetization points in the opposite direction than before, as it were decompose into an untwisted circular component and an axial component, it results that the axial component is in the opposite direction to ir direction of the magnetic field generated thereafter by word current pulses. The other one Operation of the Xagnetdrahtspeicher therefore has the consequence that now when it is rotated the direction of magnetization belonging to the rest position reduces this axial component. is even turned over.

Since there is provision, the time interval until the next change in the assignment Keeping about the same size as the previous time interval is statistical with it it is to be expected that during the following time interval those in the previous time interval Any axial component that has arisen disappears and, in the given case, also disappears in the opposite direction. The axial component then fluctuates when repeated Change of directions for magnetization between two limit values, between but who have not yet experienced any read or write problems.

The method according to the invention for operating a magnet wire storage system is obviously an advantage when it comes to storage where the binary values of stored bits in the course of normal operation or not very rarely changed. But also with magnet wire storage, where too Such changes occur more frequently in regular operation, it is to be expected that that not all of the crossing points that are used to store a bit, inevitably be affected. It is therefore advisable to use the method according to the invention to use also for the operation of such magnetic wire storage.

In order to achieve the mentioned change in assignment, e.g.

the stored bits are read one after the other at all crossing points and each time with their other previously unsaved binary value be enrolled. After that, the respective recipient is to be retained supplied read signals to change the binary value when reading supplied bits.

FIG. 3 shows an arrangement with a magnetic wire memory, at the assignment can be changed in this way.

An arrangement is assumed that has a similar structure is how known arrangements for the operation of a magnetic rotary memory (see "Development reports der Siemens-Halske-Werke ", special issue September 1969 - Rapid memory -, page 16 with Figure 3.1 and Figure 3.2). The associated magnetic wire memory P also has here Word lines Wil and magnet wire bit lines L crossing them. To a magnet wire bit line A read amplifier V, which controls a read register R, is connected to L in each case. In between, the evaluation gate S serving as an evaluation threshold is inserted. The read register R is constructed as a bistable multivibrator with parts 0 and 1 and has outputs individually assigned to the two binary values of a bit each of which the two bit driver stages TO and T1 are switched on. the one of these two bit driver stages can provide a write pulse for one and the other others a write pulse for the other binary value of one to be written Send bits via the associated Dmagnet wire bit line L. Each of the magnet wire bit lines Turns out to be these facilities, the total of the Bese writing facility Represent K. Output E is also connected to read register R, via which Read signals are passed on to recipients. Corresponding outputs are at the read registers of the other magnet wire bit lines.

The control of the read-write device K belonging to the individual Devices by control clocks is not taken into account in Figure 3, since they for understanding the invention is irrelevant.

To read the bits stored at the intersection points are the Word lines WL of the magnetic wire memory P supply word current pulses. If the If the number of word lines is large, it is advisable to do so in a manner known per se driving the word lines via a matrix; which in turn row lines and Contains column lines, at the crossing points of which the word lines Wil are connected are. This is also in the example shown in Figure 3 for an arrangement for Implementation of the method according to the invention provided. Accordingly are there the word lines WL are connected to the matrix M. From the address generator G the addresses of row lines and column lines of the matrix M are supplied, which after coding in the decoders D each have a row line and a column line supply with an In pulse, whereupon a word current pulse on the associated Crossing point connected word line is sent and thus the stored Bits are read at the crossing points of the relevant word line with the magnet wire bit lines L are stored.

It is now provided here with the read-write device K that the driver stages TO and T1 alternately to one or the other output of the read register R. can be switched on.

The connections of the bit driver stages with the outputs are for this purpose of the read register R, the changeover switches rO and rl are inserted.

Part 1 of read register R is in the position shown connected with ir bit driver stage T1 and part O with the bit driver stage TO. As a result, each bit that has been read is rewritten unchanged will. If the changeover switches rO and rl are brought into their other position, the is Part O of the read register R with the bit driver stage T1 and part 1 with the bit driver stage TO connected. This has the consequence that read bits each with their other before not stored binary value can be rewritten and so that the magnetization directions can be changed at the crossing points. This means that the same read signal as before is still supplied via output E afterwards are, the sense amplifier V is provided with two outputs at which complementary Read signals are available. After switching over the switches rO and ri, this becomes Read register R from one output to the other output of the line amplifier V with the help of the switch v. This makes the respectively delivered ones obvious Maintain read signals. In order to carry out the method according to the invention in this arrangement only the changeover switches rO, rl and v are required, which are in the predetermined time intervals are to be actuated, e.g. by means of a timer can be done. Accordingly, there are only minor interventions in the read-write device K required in order to be able to carry out the method according to the invention. The one with it associated effort is advantageously very low.

3 claims 3 figures

Claims (3)

P a t e.n t a n s p r ü c h e procedure for operating a magnet wire storage system, that of magnet wire bit lines with a magnetically used as a storage layer anisotropic surface layer and word lines crossing these magnet wire bit lines is built up and in which one bit by magnetization at each creation point the surface braid is stored in one or the other circular direction and is read out with the help of a word stream pulse generated by the associated Word line is sent, characterized in that in predetermined approximately the same Time intervals the assignment of the two circular directions (zO, zi) for the magnetization to the two binary values (0.1) of a bit is changed and that the time intervals are at least so short that de within a time interval via the word lines (WL) sent word stream impulses to no reading or writing disturbances due to distortion in the preferred magnetic direction. 2. The method according to claim 1, characterized in that that to change the assignment, the stored bits are read at all intersection points and each time with their other previously unsaved binary value to be registered and that afterwards for the further maintenance of each to recipient delivered read signals the binary value is changed when reading delivered bits. 3. Arrangement for carrying out the method for operating a magnet wire store according to claim 2, in which one sense amplifier is connected to each magnet wire bit line is connected, which controls a read register, at the two binary values one bit individually assigned two outputs individually two bit driver stages are switched on, of which the a write pulse for en one and the other a write pulse for another binary value of one to be written Can send bits over magnet wire bit lines, characterized in that each Bit driver (TO, T1) alternately to one or the other output of the Read register (R) can be switched on, so that after such a switchover the Magnetization directions are changed at the crossing points, and that the Read amplifier (V) has two outputs at which complementary read signals are available are, so that by switching the read register (R) from one to the other Output the read signals supplied in each case are retained.