CPU 315 S7 memory


Thread Starter

harith akram

what type of memory of S7 CPU315 and if I raise the memory from the cpu, what happen to the plc program

Robert D. Wagner

We would like to help, but I can't understand your question. Could you please restate it with more detail?

Robert D. Wagner, P.E.
Entry type: Download Entry ID: 37334767, Entry date: 07/09/2021
Firmware updates for CPU 315-2DP (6ES7315-2AH14-0AB0)
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Firmware updates for CPU 315-2DP (6ES7315-2AH14-0AB0) - Latest change: new firmware version V3.3.17 / Information on Functional State (FS) added

When updating the firmware, always update to the latest version available for the product and its respective article number. The previous versions of the firmware are only intended as backup to allow a downgrade to the original version. Until now this is not known to have been necessary in any case.
The respective latest version of a CPU firmware is valid for all versions of that article number.
Please note:
During the firmware update the actual values will be lost. If you require them, please save these values before starting with the FW update with the function "Copy RAM to ROM...."

The update can either be performed via Micro Memory Card or online:

1. Micro Memory Card:
Requirements for creating an operating system update card:
  • Micro Memory Card with at least 4 MB storage capacity
    article number 6ES7953-8LM31-0AA0
  • STEP 7 V5.1 SP2 or higher
  • PC with external PROM programmer (6ES7 792-0AA00-0XA0) or
    FieldPG / PowerPG for programming the Memory Card
Creating the operating system update card with STEP7:
  1. Download the desired CPU file
  2. Unpack the file by double-clicking the file name
  3. Delete the Micro Memory Card by executing: "File/S7 Memory Card/Delete" in Simatic Manager.
  4. Program the operating system by selecting "Hardware/update operating system" in SIMATIC Manager,
    then select the target directory and "open" the CPU_HD.UPD file to start the programming process.
  5. Programming of the operating system update card is completed when the message "The firmware update for the module with the article number 6ES7315-2AH14-0AB0 was transferred successfully to the S7 memory card" appears on the screen.
To update the operating system:
  1. Switch OFF the power supply (PS) of the rack in which the CPU is located
  2. Isolate the PLC from the communication network
  3. Insert the prepared operating system update card into the CPU
  4. Switch ON the power supply (PS) for the rack in which the CPU is located
  5. The operating system is transferred from the Micro Memory Card to the internal CPU flash EPROM. during this process, all indicator LEDs on the CPU are lit (FRCE, RUN, STOP, SF, BF).
  6. The operating system update is completed after about 2 minutes and is indicated by slowly blinking STOP LED => prompt for overall reset by the system
  7. Switch OFF the power supply (PS) and insert the Micro Memory Card intended for operation.
  8. Switch ON the power supply; the CPU automatically performs an overall reset and is then immediately operational.
  9. Before connecting the PLC to the communication network again the clock must be synchronized.
    2. Online:
    • An online update of the firmware is possible with STEP 7 V5.3 or higher , provided there is no safety program on the CPU or there is a safety program on the CPU and Protection Level 2 or 3 has been configured. If Protection Level 1 is configured and there is a safety program on the CPU (SDB99 exists), you require at least STEP7 V5.4 SP3 Hotfix1.
    • The module in the station whose firmware is to be updated must be accessible online.
    • A MMC (Micro Memory Card) must be available in the module as buffer memory.
    • The unpacked files with the current firmware version must be present in the file system of your PG or PC:
      A folder must only contain the files of one firmware version.
    To update the firmware:
    1. Start STEP 7 and switch to HW-Config.
    2. Open the station with the CPU to be updated.
    3. Earmark the CPU.
    4. Select the command "PLC > Update firmware". The command can only be activated, if the highlighted CPU supports the function "Update Firmware".
    5. In the dialog "Update Firmware" use the "Find" button to select the path to the firmware update files (*.UPD).
    6. Once you have selected a file, information about the module suitable for the file and the firmware version required is shown in the lower portion of the dialog "Update Firmwaree"
    7. Click on the "Execute" button. STEP 7 will check whether the selected file can be interpreted by the module; if the answer is positive, the file will be loaded into the CPU. If the operating mode of the CPU must be changed for this, you will be prompted via dialogs. The CPU will then autonomously perform the firmware update.
    8. Check with STEP 7 (read diagnostic buffer of the CPU), whether the CPU successfully starts up with the new firmware.
      Overview of article numbers and latest versions of the CPU 315-2DP:
Here some notes from a forum that can help!

I have some notes for saving the program in a PLC (card) . . .

1.) Stop the PLC. (In my case there is a 'panel application' on a PC for that purpose.)

2.) Open the Simatic Step 7 Program.
(Navigate to the desired PLC as necessary.)

3.) Go to 'blocks' and set things for 'No Filter'. (In the filter one could set it to show VAT or FB etc. etc.)

4. Go to the file menu, select 'Memory Card File' and select 'New'.
Save in the usual PC manner

5.) Name and save.

6.) Go to the window with all the blocks. Select ALL the blocks.
(highlight one file then Ctrl-A to select all)

7.) Copy and paste all the blocks into the memory card file window.
(an error message that not all the blocks will copy is normal.)

8.) Close (Save).

Application then has going back to the PLC 'Panel Application' and setting it up
such that if the PLC needs re-loading it will automatically go to the new file and reload itself.

It should be possible to open the new memory card file then
copy and paste the blocks back into the PLC as necessary.