How memory reset in CPU 414H

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How can I perform memory reset of CPU 414H

S7-400H manual

5.6 Operating sequence for memory reset

Case A: You want to download a new user program to the CPU.

1. Set the switch to the STOP position.

Result: The STOP LED is lit.

2. Toggle the switch to MRES, and hold it in that position. In this position the mode selector acts as pushbutton.

Result: The STOP LED is off for one second, then on for one second, then again off for one second, and then it remains lit.

3. Then release the switch, return it to MRES within the next 3 seconds, and then release it again.

Result: The STOP LED flashes for at least 3 seconds at 2 Hz (memory is reset) and then remains lit.

Case B: The STOP LED is flashing slowly at 0.5 Hz. This indicates that the CPU is requesting a memory reset (memory reset requested by system, e.g. after a memory card has been removed or inserted).

Toggle the switch to MRES, and then release it again.

Result: The STOP LED flashes for at least 3 seconds at 2 Hz, the memory reset is executed, and the LED then remains lit.