JPH07168756A - Memory access controller - Google Patents

Abstract

PURPOSE:To enable memory cards of different generations i.e., the ones with different capacity to be used by mixing, to enable hitherto scropped memory cards of preceding plural generations to be used, and to provide dynamic memory capacity. CONSTITUTION:This controller is constituted of a different capacity memory card control system in which an address conversion table 2 to convert an execution address from a processor to a physical address on memory, and an address conversion table initialization control part 3 which recognizes memory card capacity from a packaged memory card and performs the initialization of the address conversion table 2 are provided, and the address conversion table 2 is provided with valid bits(V:validity bit) representing the validity of a one physical memory unit(MU) and the number of the one physical memory unit(MU) and that of one logical memory unit(MU) by the number of entries.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a different capacity memory card in which a plurality of memory cards constitute a main memory device or an extended memory device and which has an address conversion table to control addresses with different capacity memory cards. Memory access control device.

[0002]

2. Description of the Related Art Conventionally, when a main memory device or an extended memory device is composed of a plurality of memory cards like a general-purpose machine,
In order to equalize the capacity of all one memory units of the storage device, it is necessary to equalize the capacity of each memory card.

Therefore, in a device having a long life such as a general-purpose machine, the generations of memories change during the manufacturing period, and the capacity per memory card increases. Therefore, when a memory card is added or replaced, memory cards of different generations must be discarded. A technique for using memory cards having different capacities in a mixed manner is disclosed in JP-A-59-124.
Reference can be made to JP-A-076 or JP-A-60-43290.

[0004]

However, the techniques disclosed in these documents do not show how to deal with address exchange of logical addresses. An object of the present invention is to provide a new memory access control device having an address conversion table for a memory device in which memory cards having different capacities are mixed.

[0005]

The first device of the present invention comprises:
Different from an address conversion table in which a physical address, a logical address corresponding to the physical address, and a validity bit indicating that at least one of the physical address and the logical address is valid are used as one set of information and a plurality of sets of information are stored. A storage unit (hereinafter referred to as a main storage device or an extended storage device) having a memory card having a storage capacity, and the capacity of the memory card mounted on the main storage device or the extended storage device via a hardware interface. And an address translation table initialization control unit for initializing the address translation table.

According to a second device of the present invention, in the first device, the address translation table initializing control unit is a memory from a memory card substantially included in the main memory device or the extended memory device via a software interface. It is characterized in that the capacity of the card is read and the address conversion table is initialized. The third device of the present invention is
An address conversion table and a memory card for storing a plurality of sets of information, each set including a physical address, a logical address corresponding to the physical address, and a validity bit indicating that at least one of the physical address and the logical address is valid. A system configuration information supply source that supplies system configuration information including the storage capacity of the memory, and an address conversion table initialization control unit that initializes the memory card capacity in the read address conversion table from the system configuration information from this system configuration information supply source. including.

[0007]

Therefore, in the memory access control device of the present invention, it is possible to use memory cards of different generations, that is, memory cards of different capacities, so that memory cards that have been discarded until now can be used. In addition, the dynamic memory capacity can be realized.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the memory access control device of the present invention will be described in detail with reference to the drawings.

Referring to FIG. 1, there is shown a concept of converting an effective address 1 from a processor into a physical address on a memory by using an address conversion table 2.

The address translation table 2 is indexed by using the upper several bits of the effective address 1 from the processor, and the physical address on the memory is created by the index result and the lower few bits of the effective address 1 from the processor.

FIG. 2 shows the address conversion table 2 shown in FIG.
The content of is shown.

The V bit indicates the validity of a physical memory unit (MU), and when the content is "1", it indicates that the MU is valid.

The physical MU # is a serial number assigned to the physical MU. In this embodiment, the physical MU # is 0-7.
There can be U.

The logical MU # is a serial number applied to the logical MU in the physical MU. In this embodiment, 1 is assigned.
There may be 0-15 logical MUs in one physical MU.

FIG. 3 shows the contents of the address conversion table 2 shown in FIG.

The V bit indicates the validity of the logical MU, and when the content is "1", it indicates that the MU is valid.

The physical MU # is a serial number applied to the physical MU. In this embodiment, the physical MU # is 0-7.
There can be U.

The logical MU # is a serial number applied to the logical MU in the physical MU, and is 1 in this embodiment.
There may be 0-15 logical MUs in one physical MU.

Referring to FIG. 4, in the first embodiment of the present invention, a pair of a physical address given to the physical memory unit described above and a logical address provided corresponding to the physical address is set. Validity indication (V) indicating whether either the physical address or the logical address is valid
An address conversion table 2 for storing a plurality of sets of information with one bit as a set, a main storage device or an expansion storage device 5 in which memory cards having different storage capacities are mixed and configured, and the main storage device or the expansion storage device 5 An address conversion table initial setting control unit 3 for initializing the memory card capacity and memory configuration information in the read address conversion table 2 from a memory card mounted on the memory via a hardware interface. In the first embodiment of the present invention, the address conversion table initialization control unit 3 reads the memory configuration information from the main storage device / extended storage device 5 via a hardware interface and initializes the address conversion table 2. To do.

Referring to FIG. 5, the second embodiment of the present invention has the same components as the address translation table 2 and the main memory device or the extended memory device 5 in the first embodiment, and the main memory device or An address conversion table initial setting control unit 4 for initializing the memory card capacity and memory configuration information from the memory card mounted in the extended storage device 5 via the software interface to the read address conversion table 2 is included.

In the second embodiment of the present invention, the address translation table initial setting control unit 4 reads the memory configuration information from the main memory unit / extended memory unit 5 into the address translation table 2 via the software interface. Make settings.

Referring to FIG. 6, the third embodiment of the present invention has the same components as the address conversion table 2 in the first and second embodiments and a source of system configuration information including the memory capacity of the memory card. 7 and an address conversion table initialization control unit 6 for initializing the memory card capacity and memory configuration information in the read address conversion table 2 from the system configuration information from the system configuration information supply source 7. In the third embodiment of the present invention, the address translation table initialization control unit 6 reads the memory configuration information from the system configuration information 7 and initializes it in the address translation table 2.

[0023]

INDUSTRIAL APPLICABILITY The present invention is effective for a memory access control device having an address conversion table for memory devices having different storage capacities, and by allowing memory cards having different capacities to coexist, it has been discarded until now. This has the effect of enabling the use of a memory card with a small capacity, which has been used for several generations.

[Brief description of drawings]

FIG. 1 is a diagram for explaining the concept of address conversion using an address conversion table.

FIG. 2 is a diagram showing an example of an address conversion table.

FIG. 3 is a diagram showing another example of an address conversion table.

FIG. 4 is a diagram showing a first embodiment of the present invention.

FIG. 5 is a diagram showing a second embodiment of the present invention.

FIG. 6 is a diagram showing a third embodiment of the present invention.

[Explanation of symbols]

 1 effective address 2 address conversion table 3, 4, 6 address conversion table initial setting control unit 5 main memory / extended memory 7 system configuration information supply source

Claims (3)

[Claims] 1. An address for storing a plurality of sets of information, with a physical address, a logical address corresponding to the physical address, and a validity bit indicating that at least one of the physical address and the logical address is valid as one set of information. The conversion table means, the storage means in which the memory cards having different storage capacities are mounted, and the capacity of the memory card is read from the memory card mounted in the storage means through a hardware interface to initialize the address conversion table means. A memory access control device comprising: an address conversion table initial setting control means for setting. 2. The address conversion table initial setting control means reads the capacity of the memory card from a memory card mounted on the storage means through a software interface and initializes the address conversion table means. The memory access control device according to claim 1. 3. An address for storing a plurality of sets of information with a physical address, a logical address corresponding to the physical address, and a validity bit indicating that at least one of the physical address and the logical address is valid as one set of information. Conversion table means, system configuration information supply source means for supplying system configuration information including storage capacity of the memory card, and memory card capacity read from the system configuration information from the system configuration information supply source means to the address conversion table means A memory access control device comprising: an address conversion table initial setting control means for initial setting.