10/23/2014 8:50 PM | |
Joined: 8/31/2010 Last visit: 5/21/2024 Posts: 1513 Rating: (223) |
Hello piddy, You got that right. An excerpt fromProgramming Guideline for S7-1200/1500as mentioned below. "S7-1200/1500 controllers have optimized data storage. In optimized blocks, all tags are automatically sorted by their data type. The sorting ensures that data gaps between the tags are minimized and that the tags are stored access-optimized for the processor. Non-optimized blocks only exist for reasons of compatibility in S7-1200/1500. Advantages: - The access is always as fast as possible, since the file storage is optimized by the system and is independent of the declaration. -No danger of inconsistencies due to faulty, absolute accesses since the access is generally symbolic. -Declaration changes do not lead to access errors since, for example, HMI accesses are performed symbolically. -Individual tags can be specifically defined as “retain”. -No settings in the instance data block are necessary. Everything is set in the assigned FB (e.g. retentivity). -Memory reserves in the data block make it possible to change the actual values without any loss Conversion between optimized and non-optimized tags: The general recommendation is to work with optimized tags. However, if you want to keep your previous programming in individual cases, this leads to a mixture of optimized and non-optimized data storage in the program. The system recognizes the internal storage of each tag, no matter if structured (derived from a user-defined data type) or elementary (INT, LREAL, etc.).In the case of type-identical allocations between two tags with different storage locations, the system converts automatically. In the case of structured tags, this conversion requires performance and should therefore be avoided, if possible." and many more. I do not have much experience withLIBNODAVE, hence I am not able to comment on it. There must be a solution out for optimized block access and 3rd party HMI very soon,may be it's taking time to lauch it. Fingers crossed.
|
Like it? Rate it! |
|
This contribution was helpful to1 thankful Users |
Follow us on