A Classification Method of High, Middle and Low Level Flash Memory

Abstract

The invention discloses a method for classifying flash memory of high, middle and low order, which comprises the following steps: firstly, using the method of automatically judging and testing the data rate of flash memory, and setting double data rate or single data rate according to the result; if the route is set as single data rate, Firstly, the bad line test is performed, and the flash memory is set to single-plane detection mode, then the flash memory is erased, and the read-write comparison classification test is performed, and finally the flash memory is classified as low-level flash memory; if the double data rate route is set, first Perform a bad line test, set the flash memory to multi-plane detection mode, then erase the flash memory and record the blocks that failed to erase, perform a read-write comparison classification test and record the blocks that failed to write; judge whether there is an erase failure block; judge whether there is a block that fails to write; judge whether there is a bad line in use, and classify it into mid-level flash memory and high-level flash memory respectively. This invention can efficiently classify high-end, high-end and low-level flash memory. nearly double.

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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