Product overview
3.4 Functions
CPU 1505SP (F) Ready4Linux Version 2.7
22 Operating Instructions, 05/2019, A5E46864285-AA
Note
Access rights on the "sda3" partition
Do n
ot change the access rights for files provided by Siemens, such as the Linux tools for
the software controller. The Linux tools are executable with standard
user rights in the
"software_controller_operators" group.
Work memory
The RAM of the PC is used for the work memory. A portion of the RAM memory is allocated
exclusively by the SIMATIC hypervisor when the CPU starts. As a result, this RAM memory
is available exclusively to the CPU. The work memory is volatile memory that contains the
code and data blocks. The work memory is permanently allocated to the CPU and cannot be
extended.
Load memory
The load memory is located in the mass storage of the PC. The CPU volume contains not
only the load memory but also internal configuration data and even retentive data, depending
on the configuration. The CPU volume is not assigned to Linux. This ensures operation of
the CPU independent of the operating system.
Retentive memory
Retentive memory is non-volatile memory for saving a limited amount of data. Retentive data
are stored on the NVRAM of a PC.
The data defined as retentive is stored in retentive memory. This data is retained beyond a
power-off.
NVRAM
When using NVRAM, saving of retentive data is possible when the CPU is shutdown
properly.
The volume of data that can be stored retentively is limited and can depend on properties of
the PC used.
CPU memory area
The CPU volume is a partition on the mass storage of the PC used. The CPU volume is
already created and has the following contents:
● Load memory,
● Configuration data
To Next Page
Loading...
Need help?
General
