View source for S7-SoftPLC:NVRAM configuration with the PLC43.INI

The NVRAM driver allows a remanent behavior of ''S7-SoftPLC''.

The driver creates a file for the retain data. Depending on the capabilities of the used file system and the size of the parameterised values, the saving process will take some time, so that the process does not take place in real-time.

See &quot;[[S7-SoftPLC:NVRAM configuration|comment on file systems]]&quot;


'''Settings in configuration file PLC43.INI'''

To activate the driver, the entry DLLn=NVRAMDLL.dll in section [OEM] must be made.

The driver expects the section [IBHNVRAM] where further parameters are defined.

{| class="wikitable"
|-
! Name of parameters !! Default value !! Description
|-
|style="width: 14em"| RemFolder(required) ||style="width: 14em"|  ||style="width: 50em"| Fully qualified path to retain data
|-
| WriteInterval(optional) || 10 || Time interval in milliseconds for the saving thread
|-
| WritePrio(optional) || THREAD_PRIORITY_IDLE || Windows thread priority for the saving thread
|-
| ShowFC(optional) || 0 || Show status block as FC
0 = SFC, 1 = FC.
|-
| SFCNo(optional) || 212 || Status block number
|-
|colspan="3"| The sign '#' is a wild-card for a number between 0 an 99
|-
| TYP#||  || Remanent type; M=Flag, D=data block, T=Timer, Z=Counter
|-
| LEN# ||  || Length of data that is kept remanent starting from address 0
|-
| DBNR# ||  || Data block number – must be given at TYP = D only
|}

Example with 1000 flagbytes, 4 counters, 8 timers and 16 bytes from DB10:

 [OEM]
 dll0=NVRamDll.dll

 [IBHNVRAM]
 RemFolder=F:\SoftPLC-NVRAM\
 TYP0=M
 LEN0=1000
 TYP1=Z
 LEN1=4
 TYP2=T
 LEN2=8
 TYP3=D
 LEN3=16
 DBNR3=10