Siemens PLC Pointer Usage

Good Day!
I am working with a data table manipulation with Siemens PLC S7 300-315 DP. I need to create an application where the data in the data block will be shifted by 1 field to the next field ( DB1.DBW0 move to DB1.DBW1, DB1.DBW1 move to DB1.DBW2 and continue.., previuos data in DB1.DBW0 will be filled with new value) I try to apply pointer p# but failed.
Please kindly advise me on the right method(code) to serve this appilcation.

Thank you.

Best Regards,
Teo WK

Hello TEOWK!

This should be posted in the Live section...

This is acutally easy... I move large blocks of data this way.

Let's say you have a DB1 with 100 words in it. To move all this info one step down you do the following:


It actually takes the first 200 bytes of db1 (starting at byte 0) and pastes it to db1 (starting at byte 2) at the next word. Hence moving the data one word down, its like shift word left or right just for large amount of data.

Hope this helps

Regards
Borte

Sorry a error in my last post...

The data has to be temporary copied to a different data area.
The source and the destination can not be overlapping.

So the code would be...


Sorry for the error....

Regards
Borte

S7 -300 and pointer usage to move data block

Thank you for your help. Borte.

It works exactly with what I need.

The code is now:

A I0.3
Fp m0.5
JCN out3

CALL SFC21
SRCBLK :=P#DB1.DBX 0.0 BYTE 10
RET_VAL:=MW30
DSTBLK :=P#DB2.DBX 0.0 BYTE 10
CALL SFC21
SRCBLK :=P#DB2.DBX 0.0 BYTE 10
RET_VAL:=MW31
DSTBLK :=P#DB1.DBX 2.0 BYTE 10

out3: NOp 0

Thanks for your great help.

Try using the function fc88 and fc 84 from the ti library