between s5 c db and s7 opn db

teh

Supporting Member
Join Date
Nov 2002
Posts
140
What is diferent between S5 C DB and S7 OPN DB?

I found that when i convert the program from s5 to s7

the function of OPN DB can only execute in that

particular network and cannot call the other data for following

network.
 
teh said:
What is diferent between S5 C DB and S7 OPN DB?

I found that when i convert the program from s5 to s7

the function of OPN DB can only execute in that

particular network and cannot call the other data for following

network.

It's the same thing, no difference. But you should be aware that if you do:

OPN DB1
L DBW 10
L DB2.DBW10

At the end of that statement DB2 will be open and not DB1. Any subsequent L DBW/DBD/DBB will load data from DB2.
 
Jeebs said:
It's the same thing, no difference. But you should be aware that if you do:

OPN DB1
L DBW 10
L DB2.DBW10

At the end of that statement DB2 will be open and not DB1. Any subsequent L DBW/DBD/DBB will load data from DB2.

LADDER_DB1.JPG




EXAMPLE,

AT NETWORK 2

I HAVE CALL A DB12

BUT AT NETWORK 3

L DBW 198 ( I HAVE LOAD NOTHING FROM DB 12)

WHY?
 
Last edited:
PeterW said:
What DB is "DIGITAL INPUT", as that is the DB that you are using in Network 3.

ACTUALLY IN NETWORK 3 ,4, 5, 6,7..I HAVE L DBW 198...200...240

MEAN EVERY NEKWORK I NEED TO ADD OPN DB COMMAND?

THIS IS THE CONVERT FILE DIRECT FROM S5 PROGRAM. I FAIL TO LOAD

THOSE DB VALUE. I FOUND THAT I HAVE TO OPN DB IN EVERY SINGLE

NETWORK..BUT IN S5 I DO NOT NEED TO C EVERY SINGLE NETWORK

EVEN PB CALLED THE DBW STILL REMAIN C DB 12

DB2.JPG
 
When you post code, please use absolute addressing - no one has to then guess at what is behind the symbol. Can you post the original step 5 for network 3 for example ?
 
Last edited:
L D[AR2 said:
When you post code, please use absolute addressing - no one has to then guess at what is behind the symbol. Can you post the original step 5 for network 3 for example ?


db4.JPG
 
i have do some minor modification for all D.I and D.O mapping to

DB. But my problem is for S5 i only c db for 1 time. and for s7

i have to opn db for every network... why?
 
Because in S5 you DO NOT open any other DB after you open DB12.

In your S7 conversion, you have placed the IO into a DB and after you open DB12, you then open DB50. So the open DB when you get to L DBW198 is DB50!!!! and NOT DB12.



EDIT:

For your info

L DB50.DBW61

is a quick way of writing

OPN DB50
L DBW61

and allows the symbolic data to be shown.
 

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