Memory reset request by the CPU
Why does my S7-300 CPU stop with a request for a memory reset after having transferred a project onto my MMC?
When a project containing an invalid block or an invalid operand for the CPU, is transfered onto the MMC, the CPU stops with a request for a memory reset.
In this situation, there is no possibility to get access to the CPU via Step 7 or to run a diagnostics. The reason for that is that the MMC (Micro Memory Card) is not deleted by the memory reset, and therefore a new memory reset is requested.
Switch the CPU to STOP. Pull the MMC out of the CPU and confirm the request for a memory reset. The memory reset of the CPU after the pull-out of the Micro Memory Card, recovers defined ratios. The CPU is now accessable communicationwise and the diagnostics buffer can be analysed .