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 .