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How to Reset the AT24C01?

What is the quickest way to make the data in AT24C01 reset to 0xFF? I write 0xFFto every byte, but that take a long time. Is there any simpler method?

In the datasheet of AT24C01: MEMORY RESET: After an interruption in protocol, power loss or system reset, any 2- wire part can be reset by following these steps:

  1. Clock up to 9 cycles.
  2. Look for SDA high in each cycle while SCL is high.
  3. Create a start condition.

I write a program just like below, but it does not work. Is it wrong? Thank you for you help! Code List:

SCL EQU P3.1 SDA EQU P3.0

ORG 00H AJMP START

ORG 30H START: MOV B,#09H CYCLE: CLR SCL SETB SDA SETB SCL DJNZ B,CYCLE CLR SDA

AJMP START END

Reply to
Loamlo
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That resets the I2C communications. Erasing the part is another matter, and I'm pretty sure since you can write individual bytes, you must erase individual bytes. This is opposed to larger parts or flash that deal with sectors.

Reply to
eepoke

If you really want to erase the entire memory, the only way is to write

0xFF. With this particular part, you can write 4 bytes in a burst to speed that up.

A simpler, faster, method may be to not erase the memory at all, but leave the old contents in there, and rewriting your code to cope with that. Perhaps you could leave some marker that indicates which part of the memory is 'free'. Whether this is possible, and how, depends on the application.

Alternatively, you could replace the part by a compatible device that allows higher erase speeds. E.g. the AT24C04 allows 8 byte bursts. Check out manufacturers datasheets.

Reply to
Artenz

Thank you very much for you help. Now I know what's the matter.

Reply to
Loamlo

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