Skip to Content

SiePortal

The integrated platform for your product selection, buying and support workflow - bringing together Industry Mall and Online Support.

SiePortalDeutsch

Search

Home
Support Support
{{(apiData.Support | filter:{'rank':1}:true)[0].title}} Support
- Menu temporary not available
- Menu temporary not available
- Menue temporary not available
- {{item.title}}

Products & Services
- Menu temporary not available
- Menue temporary not available
- {{item.title}}
Support Support
{{(apiData.Support | filter:{'rank':1}:true)[0].title}} Support
- Menu temporary not available
- Menue temporary not available
- {{item.title}}
MySiePortal MySiePortal
{{(apiData.MySiePortal | filter:{'rank':1}:true)[0].title}} MySiePortal
- Menu temporary not available
- Menue temporary not available
- {{item.title}}
Cart ({{apiData.CartCount}})

Navigation

S7-1200 DB access from function block

Created by: autom8 at: 11/4/2011 3:41 PM (10 Replies)

Rating (2)

Thanks 0

Result pages:: |; 1 | 2; |

11 Entries

Entries per page: 10 | all

11/4/2011 3:41 PM	Rate (0)
autom8 Regular Member Joined: 5/23/2008 Last visit: 10/22/2024 Posts: 8 Rating: (0)	How do you setup access to a DB in a function block with the DB number as an input to the function block. In s7-300 oneway this can bedone is bysetting input declartion as data type DB and use the OPN instruction then address directly the data in the db, DBX0.0 etc. Any ideas would be greatly appreciated!
	Last edited by: autom8 at: 11/10/2011 7:36 PM
Suggestion To thank Quote Answer

11/7/2011 1:29 PM	Rate (1)
Denilson Pegaia Diamond Expert Joined: 9/23/2005 Last visit: 1/6/2026 Posts: 4438 Rating: (1487)	Hi, See the follow example. Indirect address, of DB3.DBX4.5, MW0=DB pointer; MD10=Bit pointer: L 3 T MW0 OPN DB[MW0] ... L 37 => 4*8+5 T MD10 A DBX[MD10]
	Denilson Pegaia Siemens Industry Sector Technical Support
Suggestion To thank Quote Answer

11/10/2011 4:56 PM	Rate (0)
autom8 Regular Member Joined: 5/23/2008 Last visit: 10/22/2024 Posts: 8 Rating: (0)	Pegaia Hi, See the follow example. Indirect address, of DB3.DBX4.5, MW0=DB pointer; MD10=Bit pointer: L 3 T MW0 OPN DB[MW0] ... L 37 => 4*8+5 T MD10 A DBX[MD10] Thanks for the sugestion, I originally posted this in the S7-1200 forum and failed to mention in the message that my questionis specific to the S7-1200.

Suggestion To thank Quote Answer

11/17/2011 3:22 AM	Rate (0)
autom8 Regular Member Joined: 5/23/2008 Last visit: 10/22/2024 Posts: 8 Rating: (0)	No ideas ? Have been working on a way around this for awhile myself, surely someone has come across a way to do this...

Suggestion To thank Quote Answer

11/17/2011 5:26 PM	Rate (0)
Denilson Pegaia Diamond Expert Joined: 9/23/2005 Last visit: 1/6/2026 Posts: 4438 Rating: (1487)	Hi, Maybe rest to us just wait for SP2 (where will come SCL)...
	Denilson Pegaia Siemens Industry Sector Technical Support
Suggestion To thank Quote Answer

9/24/2013 2:17 PM	Rate (0)
plcordoba Posts: 21 Rating: (1)	Hi all! I have TIA Portal V12 SP1 Update 2. I would like to know how to do this with scl for S7 1200. Anyone can help me? Thanks!!!
plcordoba Posts: 21 Rating: (1)
Suggestion To thank Quote Answer

9/24/2013 2:47 PM	Rate (0)
0_Einstein Grandmaster-Expert Joined: 7/7/2010 Last visit: 1/6/2026 Posts: 16349 Rating: (2521)	plcordoba Hi all! I have TIA Portal V12 SP1 Update 2. I would like to know how to do this with scl for S7 1200. Anyone can help me? Thanks!!! Use the peek instruction. Look at the help for how to provide the db # and offset values. Then you can loop through the DB a byte or word at a time.
	science guy
Suggestion To thank Quote Answer

9/24/2013 3:26 PM	Rate (0)
plcordoba Posts: 21 Rating: (1)	Thanks but I know peek/poke functions. What I want to know is how to access to data from instance DB or Global DB within FBs. For example (S7300/400): L #DB_Out T #AUX_DB AUF DB [#AUX_DB] UN DBX 30.3 S DIX 30.5
plcordoba Posts: 21 Rating: (1)
Suggestion To thank Quote Answer

9/24/2013 3:34 PM	Rate (1)
0_Einstein Grandmaster-Expert Joined: 7/7/2010 Last visit: 1/6/2026 Posts: 16349 Rating: (2521)	plcordoba Thanks but I know peek/poke functions. What I want to know is how to access to data from instance DB or Global DB within FBs. For example (S7300/400): L #DB_Out T #AUX_DB AUF DB [#AUX_DB] UN DBX 30.3 S DIX 30.5 You already know the answer, peek/poke, as the only option for s7-1200. You want the STL version, you will want the s7-1500. All you need is the DB #. That said, with the portal software pushing us towards not using absolute address access and making truly universal logic programming, it seems like a revisit to the original need may help. If your logic is organized with the new way in mind, Siemens is putting the tools in place with the portal software, with custom plc datatypes, bit/byte slicing (using tag.x# and tag.b#), that should enable your problem to be solved without resorting to direct DB access. I find when I use the portal the way it was intended, it is much easier to reuse the code without any changes. When I deviate and use absolute access, my maintenance needs increase and code reuse is much more time consuming. I find bugs all the time that result from direct access. When I use custom plc datatypes, structures, dbname.tag, I find things just work out. Just a thought.
	science guy
Suggestion To thank Quote Answer

9/24/2013 5:15 PM	Rate (0)
plcordoba Posts: 21 Rating: (1)	Thanks for your reponse!
plcordoba Posts: 21 Rating: (1)
Suggestion To thank Quote Answer

|

Share this page:

Share this page on...

Follow us on