Echelon LonTal Stack - Manual (Page 141)

LonTalk Stack Developer’s Guide 129
The DMF Memory Window
To the network management tool, all content of the DMF memory window is
presented as a continuous area of RAM memory in the virtual DMF memory
space. The DMF memory space is virtual because it appears to the network
management tool to be located within the Echelon Smart Transceiver or Neuron
Chip’s native address space, even though it is not. In the code that the LonTalk
Interface Developer utility generates, the content of the DMF memory window,
which can be physically located in different parts, or even types, of the host
processor’s memory, is presented as a continuous area of memory. Another part
of the generated code identifies the actual segment within the host memory that
is shown at a particular offset within the virtual address space of the DMF
memory window, and allows the DMF memory driver to correctly access the
corresponding data within the host processor’s address space.
Data that appears in the DMF memory window includes the following:
• File directory
• Template file
• Writeable CP value files (if any)
• Read-only CP value files (if any)
The following figure shows how the different memory address spaces relate to
each other.