JPS588356A - Microprogram controller - Google Patents

Abstract

PURPOSE:To prevent incorrect renewal of an important resource due to malfunction of a microprogram, by constituting that a specific decoder is not operated until a key word is designated in the microinstruction in advance. CONSTITUTION:In revising a resource, a key word corresponding to the resource is decided in advance, and the key word is set to a specified location of the microinstruction of the 1st stage step. The detection of the key word is made with an effectiveness discrimination circuit 4 and when the key word is detected, the operation of a specific decoder 3 is permitted at the next step. If no key word is detected, the specific decoder 3 is inoperative. Thus, the destruction of the important resource due to unprepared microinstruction can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a microprogram control device for a data processing device, and more particularly to a control device that prevents important system resources from being destroyed due to microprogram errors.

Conventional microprogram control devices have the disadvantage that heavy 5e resources of devices and systems may be accidentally destroyed because they do not have any special protection function even if microinstructions are used incorrectly. In particular, in recent years, with the development of microprograms in operating systems (hereinafter referred to as O8), microprograms have become open to general users, and the risk of errors in microinstructions has increased. .

Depending on the error in the microinstruction, there is a risk that important system resources will be destroyed and the system will go down.

An object of the present invention is to prevent device and system malfunctions and system downs caused by microinstruction errors.
The object of the present invention is to provide a microprogram control device that can perform the following tasks.

The control device of the present invention includes a control memory that stores a microprogram, a microinstruction register that sequentially reads and stores microinstructions from the control memory, and a decoder that interprets the contents of the microinstruction register and outputs a required control signal. A microprogram control device equipped with a micro-instruction register compares the contents of the micro-instruction register with the keyword to determine the validity of the instruction, and enables a specific decoder operation only when the instruction is valid. Equipped with a validity judgment circuit to
The control of a specific device is characterized in that the keyword is outputted in advance using a microinstruction, and the control is performed after death.

Next, the present invention will be explained in detail with reference to the drawings.

The figure is a block diagram showing an embodiment of the present invention, reference numeral 1 indicates a control memory in which microinstructions are stored in advance, and reference numeral 2ij indicates a control memory 1 stored therein. This is a micro-instruction register that sequentially reads out 7 micro-instructions and supplies them to the decoder 3, and a decoder that decodes the 3-digit reference micro-instructions and outputs necessary control signals to cause various devices to perform necessary operations.

Generally, there are a plurality of decoders 3, and one decoder decodes a combination of a part of a microinstruction and outputs a corresponding control signal. The control signal output by a specific decoder is the main component of the system! For example, it performs update control of tables that manage the state of the system. Conventionally, if the decoder performed incorrect control due to an incorrect microprogram, the above-mentioned important resources would be unduly destroyed, and there was a risk that the system would be in an irreversible state. In this embodiment, when operating a specific decoder, in other words, when updating a resource important to the system, a keyword corresponding to the resource to be updated is determined, and the first step is to The above keyword is set in a predetermined position of the microinstruction. Then, the validity determining circuit 4 detects a keyword, and when a key read is detected, the operation of a specific decoder 3 is enabled in the next step. That is, when the keyword is detected and the specific decoder 3 does not operate, it is possible to prevent the decoder 3 from destroying the superimposed resource due to an inadvertent microphone or verbal command. Operate decoder 3*
At the ninth stage of updating the required source, the keyword association may be set in the preceding microinstruction. Even when keywords are not set, devices other than specific resources can be controlled by other decoders (not shown), so there is no problem 4 in general microprogram control.

As described above, in the present invention, a specific decoder is
Since the keyword is set in the microinstruction in advance and 411F& is applied to prevent the microinstruction from operating if it is dangerous, it is possible to prevent unauthorized updating of important resources due to malfunction of the microprogram. This has the effect of providing a highly reliable microprogram control device and preventing system failures.

[Brief explanation of the drawing]

The figure is a block diagram showing one embodiment of the present invention. In the figure, 1: control memory, 2: microinstruction register, 3: decoder, 4: validity determination circuit.

Claims (1)

[Claims] A microprogram control device comprising a control memory that stores a microprogram, a microinstruction register that sequentially reads and stores microinstructions from a key control memory, and a decoder that interprets the contents of the microinstruction register and outputs a required control signal. control of a specific device is provided with a validity determination circuit that compares the contents of the microinstruction register with a keyword to determine the validity of the instruction and enables a specific #decoder to operate only when the instruction is valid; A microprogram control device characterized in that the keyword is outputted in advance by one microinstruction and then executed.