JPH02287743A - Decision system for writing to defective memory - Google Patents

Abstract

PURPOSE:To eliminate the continuous use of the defective memory and to improve the reliability of a device by storing current address information, etc., when a storage device detects an uncorrectable error, and comparing the information with address information on a write instruction. CONSTITUTION:This system is provided with an ECC circuit 1 which can detect read data from a memory having an uncorrectable error, a storage means 2 for storing the detection of the uncorrectable error when the uncorrectable error is detected, and a storage means 3 for storing the current address information, and a recognizing means 6 which recognizes the write instruction from a processor. Further, only when the recognizing means 6 recognizes the write instruction and the storage means 2 stores the detection of the uncorrectable error, a comparing means 4 compares the address information on the write instruction with the address information of the storage means 6 and a transmitting means 16 sends the result of the comparing means 6 to the processor. Consequently, the memory where the uncorrectable error occurs can be excluded unless the process can decides that the uncorrectable error is detected.

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a write determination method for a defective memory, and in particular, it stores address information when an uncorrectable error is detected, and stores address information when a write command is received. The present invention relates to a method for determining writing to a defective memory (in which an uncorrectable error has occurred) by comparing the address with the address, and transmitting the information to a processor.

(Prior Art) Conventionally, in this type of write determination method for defective memory, when a storage device detects an uncorrectable error, it reports it to a processor;
When the processor receives a report of an uncorrectable error, it reads detailed information from the storage device, makes a determination using software, and thereafter prohibits writing to or reading from the defective memory (in which the uncorrectable error has been detected).

(Problems to be Solved by the Invention) In the conventional write determination method for a defective memory, as described above, when the storage device detects an uncorrectable error, it reports it to the processor, and the processor receives the report of the uncorrectable error. (The software determines this by reading out detailed information from the storage device and prohibits future writing to the defective memory, so it is determined that an uncorrectable error has been detected due to a failure in the storage device or processor, or a software bug.) If this is not possible, there is a drawback that writing or reading to a defective memory (which causes an uncorrectable error) cannot be recognized.In view of the above-mentioned problems of the prior art, it is an object of the present invention to prevent malfunctions in storage devices and processors. An object of the present invention is to provide a determination method that can determine a memory in which an uncorrectable error has occurred even when it cannot be determined that an uncorrectable error has been detected due to a software bug.

(Means for Solving the Problems) The present invention has the following means configuration to achieve the above object. That is, the write determination method for a defective memory of the present invention is provided in a storage device equipped with an uncorrectable error detection function; When an uncorrectable error is detected, a storage means for storing the fact that an uncorrectable error has been detected; and an address at that time. storage means for storing information; recognition means for recognizing a write command from the processor; only when the recognition means recognizes the write command and the storage means remembers that an uncorrectable error has been detected; A defective memory (in which an uncorrectable error has occurred), comprising: a comparison means for comparing address information of a write command and address information of the storage means; and a transmission means for transmitting the result of the comparison means to a processor. This is a writing judgment method.

(Example) Next, an example of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing the configuration of an embodiment of the present invention. The ECC circuit 1, which can detect that there is an uncorrectable error in the data read from the memory, that is, that there is a defective memory, outputs to the signal line 11, when an uncorrectable error is detected, the fact that an uncorrectable error has been detected. When the error storage register 2 receives a report from the signal line 11 that an uncorrectable error has been detected, it stores the fact that an uncorrectable error has been received and outputs the contents to the signal line 12. When the error address register 3 receives a report from the signal line 11 that an uncorrectable error has been detected, the error address register 3 reads the address information at that time from the signal line 15 that conveys the address information of the instruction from the processor, and stores the address of the instruction in which the uncorrectable error has been detected. It stores information and outputs the contents to the signal line 13. The write command recognition circuit 6 is connected to a signal line 16 that transmits processor commands.
It takes in the command, checks whether it is a write command, and outputs the result to the signal line 17. The comparator circuit 4 receives a report from the signal line 17 that a write command has been recognized, and only when the error storage register 2 stores an uncorrectable error from the signal line 12, compares the address information with the signal line 15. It compares the address information of the instruction in which the uncorrectable error is detected from the signal line 13, and if the results match, it is transmitted to the processor 5 through the signal line 14.

(Effects of the Invention) As explained above, when the storage device detects an uncorrectable error, the storage device recognizes the address information at that time and the storage means for storing the detection of the uncorrectable error, and a write command from the processor. The recognition means and the comparison means compare the address information of the write command and the address information of the storage means only when the recognition means recognizes the write command and the storage means remembers that an uncorrectable error has been detected. By providing a transmission means for transmitting the results of the means to the processor, even if it cannot be determined that an uncorrectable error has been detected due to a failure of the storage device or processor or a software bug, the memory in which the uncorrectable error has occurred can be handled. Since this is determined when writing is performed, there is no need to continue using a defective memory (which causes an uncorrectable error), and the reliability of the device is improved.

In addition, if all memory is checked during initial diagnosis, if the processor accidentally writes to bad memory, the storage device will determine this and notify the processor, allowing the processor to rewrite to another memory. This has the effect of not losing written data.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of a storage device that is an embodiment of the present invention. 1...ECC circuit, 2...Error storage register, 3...Error address register, 4...Comparison circuit, 5...Processor ,
6...Write command recognition circuit, lines 11-1.

Claims (1)

[Claims] In a storage device equipped with an uncorrectable error detection function; when an uncorrectable error is detected, a storage means for storing the fact that an uncorrectable error has been detected; a storage means for storing address information at that time; and a storage means for storing address information at that time; recognition means for recognizing; only when the recognition means recognizes the write command and the storage means stores that an uncorrectable error has been detected, compares the address information of the write command with the address information of the storage means; A method for determining whether to write to a defective memory, comprising: a comparison means for determining the result of the comparison means; and a transmission means for transmitting the result of the comparison means to a processor.