Echelon LonTal Stack - Manual (Page 142)

130 Developing a LonTalk Stack Device Application
Echelon Smart
Transceiver or Neuron
Chip
Registered Memory
Window
Maximum range:
0x0001 – 0xFFFF
File directory
Template file
Writable value file
Read-only value
file
unused
SNVT_address
File directory
Template file
Writable value file
Read-only value
file
Echelon Smart Transceiver or Neuron Chip
network address space
(Neuron addresses in big-endian notation)
Virtual address space: defined host-side,
using virtual Smart Transceiver
addresses in host’s byte order
Physical host address space
Address translation provided by the Interface Developer;
address translation static (by correct declaration of
SNVT_address and file directory)
Address translation provided by Interface Developer
in FtxlDev.c; translation dynamic.
LON_DMF_WINDOW_START
L
O
N_DMF_
W
INDO
W
_
U
S
A
G
E
The LonTalk Interface Developer utility defines three macros in the
generated FtxlDev.h file for working with the DMF window:
• LON_DMF_WINDOW_START
• LON_DMF_WINDOW_SIZE
• LON_DMF_WINDOW_USAGE
The LON_DMF_WINDOW_USAGE macro helps you keep track of the DMF
window fill level. The LonTalk Interface Developer utility uses this value when
it registers the actual window, whereas LON_DMF_WINDOW_SIZE defines
only the maximum window size.
You can modify the DMF framework that the LonTalk Interface Developer utility
generates to include support for user-defined files. However, all of the data must
fit within the DMF memory window.
When your data exceeds the size of the DMF memory window, you must perform
one of the following tasks:
• Reduce the amount of data
• Implement the L
ON W ORKS File Transfer Protocol
File Directory
The LonTalk Interface Developer utility produces a configurable file directory
structure, which supports: