How are the "Dynamic media addresses" (e.g. register addresses) handled by PG5?

FAQ #101533

This FAQ explains how PG5 1.4 and 2.0 handles the addresses of dynamic resources like flags and registers.

 

In PG5 it is possible to use dynamically addressed resources, for some applications it is necessary to know how these are handled.

When are the "dynamic" addresses assigned?
In general PG5 starts at the beginning of the dynamic address range (which can be defined in the "Build Options" of the CPU) and uses continuous increasing addresses. The sequence with which the resources are addressed is not directly given by the place of their appearance or index in the name.
Once an address has been assigned to a symbol, this symbol will keep its address until

  • it is deleted or 
  • a "Clean Files" is executed. 
  • The device (CPU) is renamed 

In which case are addresses re-used?
When resources are deleted, the (previously) used addresses are freed directly after a new build. This means that new added resources will use the same address another symbol had before. In some cases this can cause some problems e. g. when other devices or software accesses dynamic addressed symbol by their real address.

Conclusion
For this reason, resources which are accessed from the exterior should always be addressed statically.
 

 

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PG5 2.0 / Symbol Editor

Last update: 31.05.2015 00:53

First release: 26.11.2010 09:00

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