5.5
374 Flash EPROM Cards
This section provides a summary
••
of the use of the 374 flash EPROM cards (known as the 374
memory cards in the following) in the CPU 948,
••
and of the technical specifications.
5.5.1
Technical Description
The 374 memory card serves as a storage medium for user programs
and user data. It contains electrically erasable flash EPROMs.
The 374 memory card is available in the following capacities:
••
256 Kbytes
••
512 Kbytes
••
1024 Kbytes
••
2048 Kbytes
••
4096 Kbytes
Ordering information
The order numbers for the SIMATIC S5 memory cards can be found
in the ordering information.
5.5.2
Notes on Operation
Programming a
memory card
You can program and erase the 374 memory card off-line on the
SIMATIC S5 programmers. The link to the PG is provided by a
special connector or programming adapter, into which the memory
card is inserted. A description of EPROM programming can be found
in the STEP 5 manual.
Inserting and removing a
memory card
Memory cards can be inserted and removed at any time, even whilst
the CPU is running, as long as they are not being accessed (see the
CPU 948 Programming Guide).
Loading data
The contents of the memory cards are only copied automatically into
the internal RAM of the CPU upon overall reset of the CPU.
Erasing a memory card
Memory cards are electrically erasable.
5
374 Flash EPROM Cards
System Manual
C79000-B8576-C199-03
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