JPS62117048A - Control system for memory device - Google Patents

Abstract

PURPOSE:To attain detailed test/diagnosis by means of various complicated test patterns without using any test-only memory, by using a key memory in a maintenance/diagnosis mode. CONSTITUTION:A key memory 11 generally stored the memory protecting information of about 3 bits for each page unit (2-4K bytes) of the memory space of a main memory. A maintenance diagnosis device device 2 serving as a microprogram storing means extracts a maintenance/diagnosis microprogram out of a file memory in a maintenance/diagnosis mode of a memory device and stores it in the memory 11. A self-test/diagnosis circuit 12 produces the test writing signal to a main memory and checks the output signal. A microprogram control means 13 uses a maintenance/diagnosis program stored in the memory 11 to control a self-test/diagnosis circuit 13. The test/diagnosis microprogram has the function to perform the +1 and -1 shifts, the bit inversion, etc. to a test address register and a write data register of the circuit 12.

Description

[Detailed Description of the Invention] [Summary] In a storage device equipped with memory protection storage (hereinafter referred to as key memory) for memory protection, a microprogram for maintenance and diagnosis of the storage device is stored in the key memory during maintenance and diagnosis. This microprogram is used to perform detailed maintenance and diagnosis using various test patterns.

INDUSTRIAL APPLICATION FIELD The present invention relates to a test/diagnosis method for a storage device equipped with a key memory for storage protection.

In a storage device, access control information and information indicating the validity of each section (hereinafter referred to as a page) of a storage space are stored as a unit, and this information is referenced to access each corresponding page of the storage space. Increasingly, storage is protected by controlling access to the computer.

The key memory stores the storage protection information for each page.

The present invention aims to improve the accuracy of testing and diagnosis by utilizing this key memory when testing and diagnosing storage devices.

[Prior Art] Conventionally, testing and diagnosis of storage devices have been performed using built-in test equipment using hardware logic, mainly for economical reasons.

Therefore, only a limited number of tests and diagnoses could be performed using relatively simple test patterns. [Problems to be solved by the invention] As mentioned above, conventional test equipment using hardware logic However, it was only possible to perform tests and diagnoses using simple test patterns, and highly accurate tests and diagnoses were not possible.

A read signal of a memory element in a storage device is small and fast, and the influence of fluctuations in power supply voltage and noise cannot be ignored. It also changes depending on conditions such as the pattern of information to be stored and the order of addresses.

Therefore, in order to ensure reliability of memory, it is necessary to perform detailed tests and diagnosis.

For example, the power supply voltage is set to +5% and -5% of the specified voltage, and several types of specific information patterns are tested by reading/writing them, and the addresses are not simply ascending or descending order, but are tested in a specific order. By testing by making complex changes according to a promise, it is possible to discover potential faults in the memory.

The present invention aims to provide a storage device control method that utilizes a key memory during testing and diagnosis to perform such highly accurate testing and diagnosis.

[Means for Solving the Problems] FIG. 1 shows a block diagram of the principle of the storage device control system of the present invention.

In FIG. 1, 1 is a storage device, 10 is a main memory, and 11 is a key memory.

Key memo January 1 is usually a page (2) in the main memory storage space.
(4 bytes) Stores about 3 bits of α protection information per company. Therefore, for example, if the storage space of the main memory IO is 1 Mbyte and the page is 2 bytes, the capacity of the key memory 11 is 1.5 bits.

Reference numeral 2 denotes a maintenance/diagnosis device that functions as a microprogram storage means, and corresponds to the service processor included in many recent electronic computer systems.

At the time of maintenance/diagnosis of the storage device, the maintenance/diagnosis device 2 takes out the maintenance/diagnosis microprogram from the file memory and stores it in the key memory 11.

Reference numeral 12 denotes a self-test/diagnosis circuit which generates a test write signal to the main memory and checks a read signal.

Reference numeral 13 denotes a microprogram control means, which controls the self-test/diagnosis circuit 13 using a maintenance/diagnosis microphone [J program stored in the key memory 11].

Reference numeral 14 is a memory control circuit which controls writing and reading from the main memory, and also writes key memo data when specified.
to manage access for storage protection.

Reference numeral 2 denotes a storage control device that prioritizes and controls access requests to the storage device 1 from the central processing unit and channel devices.

[Operation] As explained above, during maintenance diagnosis, the test/diagnosis microprogram is stored in the key memory.

The test/diagnosis microprogram is provided with functions to perform +1, -1, shift, bit inversion, etc. on the test address register and write data register of the self-test/diagnosis circuit.

Using this test/diagnosis microprogram, it is possible to generate various test patterns and perform a wide variety of JX tests/diagnoses.

[Example] The present invention will be described in more detail below with reference to Examples shown in FIGS. 2 and 3.

FIG. 2 is a block diagram of an embodiment showing details of the microprogram control circuit and self-test/diagnosis circuit of the present invention.

In FIG. 2, 10 is a main memory, and 11 is a microprogram storage unit, in which a microprogram is stored in a key memory.

13 is a microprogram sequencer, the first
This corresponds to the microprogram control section in the figure.

Reference numeral 14 denotes a storage control section, which is the same as that in FIG.

121-127 are the main components of the self-test/diagnosis circuit.

When performing main memory maintenance diagnosis using the system shown in Figure 2,
This is done through the following operating steps:

(1) First, the storage device is logically separated from the storage control device so that it can be controlled by the maintenance/diagnosis device.

(2) Store the storage device maintenance/diagnosis microprogram from the maintenance/diagnosis device into the key memory.

(3) The self-test/diagnosis circuit is started by instructing the microprogram control circuit (microprogram sequencer) to start from the maintenance/diagnosis device.

(4) The microprogram control circuit (microprogram sequencer) 13 reads the next microprogram to be executed from the designated address of the microprogram storage unit (key memory) 11 and stores it in the microprogram register 121.

(5) The microprogram controls the test address generation circuit 22, the test write data generation circuit 123, the continuous check data generation circuit 124, and the test command generation circuit 125 to send addresses to the storage control circuit I4, respectively; Create write data, commands, and continuous check data.

(6) The comparison circuit 127 compares the successive data in the successive data register 126 and the data generated by the successive check data generation circuit 124, and sends the result to the microprogram sequencer (control circuit) 13.

(7) The microprogram control circuit (microprogram sequencer) 13 is connected to the test address generation circuit 12.
2. The specified address of the microprogram to be executed next is determined based on signals from the comparison circuit 127 and other check circuits and the currently executing microprogram.

(8) The following operations (4), (5), (6), and (7) are executed until the operation is stopped by a stop command or a signal from the check circuit.

FIG. 3 is a diagram showing an example of the formant of microinstructions used in the maintenance/diagnosis microprogram of the present invention.

The microinstruction consists of six fields: (1) microprogram sequencer control section, (2) offset, (2) address control section, (2) write data control section, (2) continuation check data control section, and (2) command control section.

It is assumed that each field has a number of bits that can represent each function type.

[Effects of the Invention] As explained above, according to the present invention, by using the key memory during maintenance and diagnosis, detailed tests and diagnoses can be performed using various complex test patterns without having a memory dedicated to tests. It has become possible to do so, and its practical effects are extremely large.

[Brief explanation of drawings]

FIG. 1 is a block diagram of the principle of the present invention, FIG. 2 is a block diagram of an embodiment of the present invention, and FIG. 3 is a diagram showing an example of the format of a microinstruction. In the drawings, ■ is a storage device, 2 is a maintenance diagnostic device, 3 is a TV control device, 10 is a main note/[, α, 11 is a key memory (microprogram storage section), 12 is a self-test/diagnosis 13 is a microprogram control circuit (microprogram sequencer), 14 is a storage control circuit, 121 is a microprogram register, 122 is a test address generation circuit, 123 is a test write data generation circuit, and 124 is a continuous check data generation circuit. 125 is a test command generation circuit, 126 is a successive data register, and 127 is a comparison circuit. Ki fl! Ill/”1
Figure 1: Block diagram of the principle of the present invention

Claims (1)

[Scope of Claims] In a storage device equipped with a protected memory that stores access control information and information indicating the validity of the access information in units of a certain partition of a storage space, when the storage device is maintained and diagnosed, means for storing a microprogram for maintenance diagnosis of the main memory in the protected memory; a self-test/diagnosis circuit for generating a test write signal to the main memory and checking a read signal; 1. A storage device control system comprising: microprogram control means for controlling the self-test/diagnosis circuit using a maintenance/diagnosis microprogram, and configured to test/diagnose main memory.