Method for classifying high, medium, and low order flash memory

Abstract

The invention discloses a classification method of high-middle and low-order flash memory, which comprises the following steps: firstly, using a method of automatically judging and testing data rate of flash memory, setting double data rate or single data rate according to the result; secondly, using the method of automatically judging and testing data rate of flash memory. If the data rate is setto single data rate line, the bad line test is carried out first, the flash memory is set to single plane detection mode, then the flash memory is erased, the read / write comparison test is carried out, and finally the flash memory is classified to low-order flash memory. If the dual data rate route is set, the bad line test is first performed, and the flash memory is set to the multi-plane detection mode. Then, the erasing block of the flash memory is erased and the erasing failure block is recorded, and the read / write comparison test is performed and the writing failure block is recorded. Determining whether there are blocks that fail to erase; whether there are blocks that fail to be written is determnined; the invention can efficiently classify the high, middle and low-order flash memories, and the classification speed is nearly twice as high as that of the traditional classification method.

Description

technical field [0001] The invention relates to the technical field of flash memory classification methods, in particular to a classification method for high, middle and low order flash memories. Background technique [0002] Flash Memory (Flash Memory) is a long-life non-volatile memory (it can still maintain the stored data information in the case of power failure). Data deletion is not in single byte units but in fixed blocks. (Note: NOR Flash is stored in bytes.), the block size is generally 256KB to 20MB. Flash memory is a variant of electronically erasable read-only memory (EEPROM). The difference between flash memory and EEPROM is that EEPROM can be deleted and rewritten at the byte level rather than the entire chip. Most chips of flash memory need block erase remove. Because it can still save data when the power is off, flash memory is usually used to save setting information, such as saving data in the computer's BIOS (basic program), PDA (personal digital assista...

AI Technical Summary

Problems solved by technology

[0003] Flash memory is composed of blocks, and each block is divided into multiple pages. Each page is composed of multiple columns. In addition, pages that cannot be read and written normally are bad pages, and all pages are bad. The general classification method can only simply classify high-level or middle-low level flash memory particles. If a group of particles needs to be clearly divided into high-level, high-level and low-level levels, two sets of methods will be used, which will take nearly twice the time.

Especially the particle capacity is increasing day by day, the cost of time spent is very alarming, therefore, an improved technology is urgently needed to solve this problem existing in the prior art

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