Siemens Step 7 - Get Data

Hello World

Have a bit of an unusual problem.

On a project currently being developed I have been issued with blocks that MUST be used, however some of the glue that holds it all together has not been issued, and also refused to be issued.

One of the requirements is to get acyclic data from a Simocode, this is embedded in the block, reading four records and writing one.

The vital bit that is missing is the mechanism for getting this data.

I think to do this I must set up a routine to set a read bit for a drive with data block, start address to use and possibly the length. At completion this will increment a counter and repeat for the next drive for reading. Writing will be via a bit from the HMI so a little more straight forward.

What is evading me at the moment is what instruction to use and also how to ensure the right data record is stored in the right area of the data block.

Any thoughts or advice would be appreciated.

Very hard to say without seeing blocks itself.

Not really able to share blocks as have a limited access to them.

In essence the block takes the cyclic data and manages the start stopping etc.

Within the block is an acyclic read/ write function which contains four instances of SFB52 (one per report) and one of SFB53.

As these in the 'Simocode' function block I need:
1. Set bit externally for Acyclic Read/ Write
2. Get data from Simocode and populate selected Data Block
3. Store data in correct area.

As the actual function for acyclic data is embedded in the block I need to set the read/ write parameters outside the block.

I am just uncertain about how to get the data from the Simocode into the data block, via a function block. What command would be best utilised to interogate the function block and extract the information.