WO1990006580A1

WO1990006580A1 - Electro-mechanical data store

Info

Publication number: WO1990006580A1
Application number: PCT/EP1989/000601
Authority: WO
Inventors: Günter Baitz; Wolfgang Kern
Original assignee: Siemens Nixdorf Informationssysteme Ag
Priority date: 1988-11-28
Filing date: 1989-05-30
Publication date: 1990-06-14
Also published as: KR930008152B1; EP0445115A1; JPH03505942A; DE8814802U1; KR900702535A

Abstract

The invention concerns an electro-mechanical data store comprising a first and a second storage unit (50, 52), each with a storage medium the position of which can be changed by means of a drive, and further comprising a drive control unit and a read/write device associated with the storage medium. One of the storage units (50, 52) is an encapsulated fixed-disc mechanism and both of the storage units (50, 52) are mounted in the same rack. The storage units (50, 52) are mounted on each side of the same baseplate (56), which forms part of the rack, and at least parts of the electronic control circuits for both storage units (50, 52) are mounted on a common circuit board (84).

Description

Electromechanical data storage device

The innovation relates to an electromechanical data storage arrangement comprising a first and a second storage unit, each with a storage medium adjustable by a drive, a drive control and a read / write device assigned to the storage medium, the storage units being arranged in a common frame.

A data storage arrangement of the aforementioned type known from EP-A-69 545 comprises two functionally separate storage units which are self-contained. One is a hard disk drive and the other is a cassette tape drive that can be fully inserted into the frame of the hard disk drive. Both can have an appropriate one 1 interface can be functionally coupled. Since the two storage units form completely independent units in terms of space and function, which can also be produced independently of one another, the space is

5 may still be relatively high for both units. Functionally, they behave like any two storage media that can be connected to one another by an interface.

A higher form of integration of two storage units 0 is realized in the data storage arrangement described in EP-A-20 176. A hard disk drive and a tape drive are also combined here, the read / write drum for the magnetic tape of the tape drive being arranged on the shaft of the hard disk drive 5. A functional connection is provided between the two storage units, which allows data to be transferred directly from one storage unit to the other. This embodiment allows the spatially dense and compact arrangement of the Speichereinhei- ⁰ th. Functionally, however, this embodiment has the disadvantage that the storage units are not independently operable. As a result, the possible uses of the storage units and thus also the performance of the entire data storage arrangement become significant

^• - 'restricted.

The innovation is based on the object of specifying a data storage arrangement of the type mentioned at the outset which is so compact in space that it does not exceed a height of 41.3 mm 30 (so-called half-height) without the performance of the data storage arrangement being restricted . According to the innovation, this object is achieved in that both storage units are arranged on the two sides of a base plate of the frame common to them and at least parts of the electronic control circuits of both storage units are arranged on a common printed circuit board. This enables an extremely compact arrangement of the data memory, since the common base plate can be shaped in such a way that cavities in one memory unit can be used to accommodate components of the other memory unit. This makes it possible to accommodate a hard disk drive and, for example, a tape drive in a device insert with a height of 41.3 mm, ie the so-called half height, which previously could only accommodate one hard disk drive alone. Instead ^e: .ines tape drive can also be a Wechselplatten¬ drive (floppy disk drive) or a device for optical storage of data is provided, the storage medium is each replaceable.

The spatially close arrangement of the two Speicherein¬ units and the accommodation of electronic Schaltungs¬ parts of both storage units on a common circuit board, it is possible in a particularly simple manner, the memory units also functionally closely __ ^■ __ connect by the two memory units through an internal bus are connected to one another and to a common interface, via which the data memory can be connected to a data processing system, and a common sequence control is assigned to both memory units, the data transport on the internal bus and the access to the two memory devices units by one between the internal bus and the - A -

Sequence control arranged bus control with intermediate storage function is controllable.

The main advantage of this solution is that, on the one hand, each storage unit can be accessed individually via the interface and, on the other hand, data can be exchanged between the storage units via the internal bus without the need to transport data via the interface. The bus control and the sequence control common to the two storage units ensure that the available times for the data transport between the interface and the individual storage units, between the storage units among one another and between the interface and the bus control are optimally used.

A bus protocol unit which isolates them from the internal bus is preferably arranged between the internal bus and the interface. The latter has the task, for example, of first collecting and building up incoming commands via the interface and only then passing them on to the bus controller via the internal bus, in order to keep the internal bus free for internal data transport as long as possible. For example, a SCSI interface can be used as the interface.

A read / write memory is preferably connected to the internal bus and serves as a buffer for the data read from a memory unit or for data to be stored in a memory unit. This enables problem-free transfer of the data from one storage unit to the other. While the hard disk drive is mainly used as background memory due to its short access times, the other storage units with their exchangeable data carriers either allow the data of the hard disk drive to be backed up or data records and programs can be transferred to the hard disk drive, with the functional connection of the two memories ¬ units guarantee extremely short transmission times via the internal bus and the computer bus is not loaded.

The following description, in conjunction with the accompanying drawings, explains the innovation on the basis of exemplary embodiments. Show it:

Fig. 1 is a block diagram of the innovation

Data storage arrangement,

2 shows a section through a data storage arrangement according to a first embodiment of the invention along line II-II in FIG

Figure 3,

3 shows a plan view of the arrangement shown in FIG. 2 in the direction of arrow A,

Fig. 4 is a plan view of the arrangement according to

2 in the direction of arrow B,

5 to 7 representations corresponding to FIGS. 2 to 4 of a second embodiment of the data storage arrangement according to the invention and 8 to 10 representations corresponding to FIGS. 2 to 4 of a third embodiment of the data storage arrangement according to the invention.

In Figure 1, the dashed rectangles 10 and 12 denote two storage units. The storage unit 10 can be, for example, a hard disk drive, while the storage unit 12 is, for example, a removable disk or floppy disk drive (floppy disk drive), a tape drive or an optical storage device, as is shown in FIG of Figures 2 to 10 is described in more detail. The two storage units 10 and 12 are connected to one another via an internal bus 14 and via an interface 15 to a peripheral bus 16, which may be a SCSI bus, for example. The connection between the internal bus 14 and the peripheral bus 16 takes place via a bus protocol unit 18, which is capable of independently receiving and temporarily storing a command with its auxiliary parameters, and through which the internal bus 14 is isolated from the peripheral bus 16. The data transport on the internal bus 14 is controlled by a bus controller 20 with a buffer function. The bus control is via a processor bus 22 with a Microprocessor 24 connected, which is responsible for the sequential control of the entire data storage arrangement. The microprocessor 24 contains a small internal read / write memory and receives commands from the read-only memory 26 via the processor bus 22. By separating the processor bus 22 from the internal bus 14, this can be done independently of a simultaneous data transport on the internal bus 14 done.

10 Each of the storage units 10 and 12 comprises a formatter 28 and 30, respectively, which communicates with the internal bus 14 and converts the data format on the internal bus 14 into that of the storage medium and vice versa, and data in each case to a data channel 32 or 34 can send or receive from this. The data channels 32 and 34 each encode or decode the data between the NRZ format (non return to zero) and the write format on the storage medium. Write ver¬ with the data channels 32 and 34 Thematic read / write devices 36 and 38 / read the encoded data to the respective storage medium _> o ^Δυ or from this. The storage media are each moved by a mechanism with an associated control 40 or 42, which in turn derives its commands from the

Microprocessor 24 received via lines 44, 46 and

Submit status reports to them. 5

When a command arrives from the peripheral bus 16, it is first temporarily stored in the bus protocol unit 18 until it has arrived completely. During this time, the internal bus 14 and the microprocessor 0 24 are free for other tasks. After the command has arrived completely, the microprocessor 24 is prompted to process the command and, if necessary, to send commands to the mechanical controls 40 and 42. Around the peripheral bus 16 To keep it as long as possible and to burden it as little as possible due to processes within the data storage arrangement, when writing information to the storage media, first a read / write memory 48 connected to the internal bus 14 is filled, and only then is the respective memory medium from this read / write memory 48 described. Conversely, data that are read from the storage medium are first stored in the read / write memory 48 and then transferred to the peripheral bus 16 at maximum speed via the bus protocol unit 18.

With skillful organization of the accesses by the bus control 20, it is even possible to transmit a newly arrived command from the bus protocol unit 18 into the microprocessor 24, while quasi - at the same time one of the formatter 28 and 30 data in or out of the write / Read memory 48 transfers.

The data paths 18, 14, 20 and 48 common to both storage units 10 and 12 and the central sequence control by the microprocessor 24 allow a special mode of operation which makes the data storage arrangement shown particularly suitable for the production of security copies (backup copies). With a special command, data can be copied from one storage medium to the other without the peripheral bus 16 being burdened with the data transmission. Here, the one formatter 28, 30 fills the read / write memory 48 when reading from its storage medium, while the other (30, 28) empties the read / write memory 48 when writing to the associated storage medium. For each of the mechanical controls 40, 42, the microprocessor 24 knows when an interruption is likely to occur in the data flow to or from the respective storage unit 10, 12 (for example, due to positioning times, starting or braking of the belt, etc ). If these unusable times are now coordinated with one another in such a way that the read / write memory 48 working as a buffer is filled and emptied as evenly as possible, this results in a good utilization of this buffer memory and a fast processing of this special type of command.

Figures 2 to 10 now show three embodiments of a data storage device comprising two storage units that are particularly space-saving combined and functional - tional are connected to each other in the manner described above. ¹

The embodiment illustrated in Figures 2 to 4 shows a combination of a hard disk drive 50 with ^υ a tape drive 52. The hard disk drive comprises a housing base 54 having a base plate 56 on which the two magnetic plates 58 carrying drive motor is arranged 60th Furthermore, a drive 62 for support arms 64, which carry the magnetic heads 66 for the individual magnetic plates 58, is mounted on the base plate 56. The lower housing part 54 is closed by a housing cover 68. The structure of a hard disk drive of the type described above is known per se, so that further explanations of the drive are not necessary.

The basic construction of the tape drive is also known. It comprises a belt drive with a drive motor 70 and a gear 72, with motor 70 and the elements of the transmission 72 are attached to the base plate 56. As can be seen in FIGS. 2 and 3, the base plate 56 has a shape 74 in a corner region which projects into an unused cavity of the hard disk drive 50. This creates sufficient space to accommodate the tape drive motor 70 so that the tape drive 52 can be kept very flat overall.

Between an intermediate plate 76 covering the tape mechanism 70, 72 and the top surface of a drive housing 78, a shaft 80 is formed, which serves to receive a tape cassette 82, which in the direction of arrow C in

Figure 2 can be inserted into the shaft 80.

The above description shows that by using the same base plate 56 for the storage of the mechanical parts of both drives 50 and 52 and by using cavities in one drive for accommodating parts of the other drive, the overall height is very low Data storage arrangement results. This effect is reinforced by the fact that the electronic controls for both drives are arranged on a common printed circuit board 84 which is screwed onto the housing cover 68 of the hard disk drive 50 and carries an electrical connection device 86 via which both storage units 50 and 52 are connected to one Data processing system can be connected.

The embodiment according to FIGS. 5 to 7 differs from that according to FIGS. 2 to 4 only in that a floppy disk drive 88 is now combined with the hard disk drive 50 instead of the tape drive 52. The parts which correspond to the arrangement according to FIGS. 2 to 4 are again provided with the same reference symbols. The floppy disk drive 88 is also known per se and is therefore only explained schematically. It comprises a drive motor 90 arranged on the base plate 56 for a floppy disk 93 which can be inserted into a guide shaft 92 in the direction of the arrow D in FIG. Read / write heads 94, which can be positioned via a positioning drive 96, are used for writing and reading data to and from the diskette. Space for accommodating the positioning drive 96 was gained by accommodating it in a protuberance 98 in the base plate 56, which protrudes into an unused cavity in the disk drive 50. The electronic components common to the two drives 50 and 88 are in turn arranged on a printed circuit board 84 which is attached to the hard disk drive 50.

In the embodiment shown in FIGS. 8 to 10, a hard disk drive 50 is combined with a disk drive for an optical storage disk. This storage unit 100, which is also known in principle in its own right, comprises a drive motor 102 for an optical storage disk 106 which can be inserted into a guide shaft 104. The optical read / write head 108 can be positioned relative to the optical storage disk 106 via a positioning drive 110, whereby the positioning drive 110 is again arranged in a depression 112 of the base plate 56 protruding into the hard disk drive 50 in order to reduce the overall height of the entire storage arrangement. Otherwise, the embodiment according to FIGS. 8 to 10 corresponds to the embodiment according to FIGS. 2 to 4 and 5 to 7.

Claims

80-12 claims

1. Electromechanical data storage arrangement, comprising a first and a second storage unit (10, 12), each with a storage medium adjustable by a drive, a drive control (40, 42) and a read / write device (36, 38) assigned to the storage medium. , wherein one of the storage units is an encapsulated hard disk drive and the storage units (10, 12) are arranged in a common frame, characterized in that the storage units (50, 52; 50, 88; 50, 100) on the two Sides of a common base plate (52) of the frame and at least parts of the electronic control circuits of the two memory units (50, 52; 50, 88; 50, 100) are arranged on a common printed circuit board (84).

2. Data storage arrangement according to claim 1, characterized in that the second storage unit is a magnetic tape storage (52).

3. Data storage arrangement according to claim 1, characterized in that the second storage unit is a removable disk drive (88).

4. Data storage arrangement according to claim 1, characterized in that the second storage unit has an optical storage medium (106), _εu f or from which the data can be transferred or removed by means of an optical read / write device (108, 110).