Choose Your migration tactics, as there are several migration options.
Choosing way to go depends on several factors:
1. Developers skill and experience level.
2. Complexity of process or machine.
3. If process/machine is functional prior to migration.
4. Availability/Accessibility of an old S5 software.
Official Siemens S5 to S7 migration tool is available, but in most cases it will not be able to autonomously complete migration without developers intervention.
Migration tool will not be able to compile new technology objects and functions that use programming practices that were not common during S5 era.
In most cases, except for most simple applications, developer will have to roll up sleeves and have focused approach to this task, while Migration tool might be used only to speed up migration process or it will not be used at all.
In following two personal examples I will show different examples of S5 to S7 migration, covering different approaches whose selection is based on machine concept.
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