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Entry type: FAQ Entry ID: 21829579, Entry date: 03/05/2010

Which devices can you use to read from, write to or delete from an S7-300 MMC (Micro Memory Card) outside the CPU?

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Device note
The SIMATIC Micro Memory Cards (MMCs) of the S7-300 may be read or written only by the following devices outside the CPU:

  • SIMATIC Field PG
  • SIMATIC Power PG
  • USB prommer (order number 6ES7792-0AA00-0XA0).

Using these devices, you can open an MMC in the SIMATIC Manager for reading or writing or for deleting the content.

Fig. 01

Do not use the MMC for non-SIMATIC purposes and do not format it with a third-party device. This would possibly overwrite the internal structure of the MMC that cannot be restored. In this case, the MMC is no longer recognized/accepted in a SIMATIC S7-300 CPU and can no longer be used with SIMATIC devices.

More information on handling the MMC is available in the manual "S7-300, CPU 31xC and CPU 31x: Installation Instructions" in Entry ID 13008499.

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