Embedded recall apparatus and method in nonvolatile memory

A method for verifying data stored in a memory, the method comprising:

• receiving a power on reset signal;
• reading data from a first predetermined location of the memory;
• reading a memory pattern from a register;
• comparing the read data and the read memory pattern to determine whether there is a match;
• resetting a read count state in the event there is not a match;
• incrementing said read count state in the event there is a match;
• repeating said reading, comparing, resetting and incrementing in the event the count state is less than a predetermined maximum count value;
• reading data from a second predetermined location of the memory;
• incrementing a read pass count;
• and
• repeating said reading, comparing, resetting and incrementing in the event the read pass count is less than said predetermined maximum count value.

A memory device comprising:

• means for storing data;
• means for reading data stored in a first location of the means for storing in response to an initiation signal;
• means for comparing the read data and a predefined data pattern to determine whether there is a match;
• and
• means for repeating said reading and comparing in the event that said comparing determines consecutive matches less than a predetermined number of matches.

A memory device comprising:

• means for storing data;
• means for reading data a predetermined location of the means for storing in response to a power on reset signal;
• means for reading a memory pattern from a register;
• means for comparing the read data and the read memory pattern to determine whether there is a match;
• means for resetting a read count state in the event there is not a match;
• means for incrementing said read count state in the event there is a match;
• means for repeating said reading, comparing, resetting and incrementing in the event the count state is less than a predetermined maximum count value;
• means for reading data from another predetermined location of the means for storing;
• means for incrementing a read pass count;
• and
• means for repeating said reading, comparing, resetting and incrementing in the event the read pass count is less than said predetermined maximum count value.

A memory device comprising:

• a memory;
• a first register storing a predefined data pattern;
• a first comparator coupled to the first register and the memory to command a read therefrom and generating a match signal indicating a match in the event the data read from a first location of the memory matches the predefined data pattern and indicating a non-match in the event the data read from the first location does not match the predefined data pattern in response to an initiation signal and;
• a first counter coupled to the comparator to cause the first comparator to command a read and generate said match signal in the event that said match signal does not indicate a match for a predetermined number of consecutive reads.

A method for verifying data stored in a memory, the method comprising:

• receiving a power reset signal;
• reading data stored in a first location of the memory;
• comparing the read data and a predefined data pattern to determine whether there is a match;
• reading data stored in a second location of the memory;
• comparing said read data stored in said second location and previously read data stored in said second location;
• repeating said reading and comparing in the event that said comparing of read data of the first location determines consecutive matches less than a first predetermined number of matches;
• resetting said count of consecutive matches in the event that the number of consecutive matches is equal to or greater than said first predetermined number of matches and that said comparing said read data stored in said second location and previously read data stored in said second location match;
• repeating said read and comparing of data stored in said second location in the event that said count of consecutive matches is less than said first predetermined number of matches and the number of matches of said comparing said read data stored in said second location and previously read data stored in said second location is less than a second predetermined number of matches.