Echelon FTXL - Manual (Page 199)

FTXL User’s Guide 187
Table 53. Non-Volatile Memory Required for the Application Data
Application Data Bytes Required
Header 16
CPNVs
( )
∑
j
j
CPNVlen
File-based CPs File_length
Application-specific data Data_length
Notes:
• CPNVs are configuration property network variables
• File-based CPs are configuration properties that are defined in
configuration files
• CPNVlen
j
is the configuration network variable (CPNV) length of a
specific CPNV value – the application data includes the sum of the CPNV
lengths of all CPNV values
• File_length is the size of the writeable configuration file for the
configuration properties
• Data_length is the length of any addition application-specific data
Memory Usage Examples
Table 54 on page 188 shows the amount of RAM and flash that are required for
various example FTXL applications. Each row of the table represents a different
application by varying the number of network variables, transmit transactions,
receive transactions, aliases, and address table entries. The values for all
columns except the network variable column represent values calculated by the
LonTalk Interface Developer utility.
The table assumes that each network variable has a length of 2 bytes, and has a
5-byte self-documentation string associated with it. The table also assumes the
default number of application buffers (5 input buffers, 5 output nonpriority
buffers, and 1 output priority buffer). Varying the number of application buffers
does not siginificantly alter the amount of RAM that the application requires,
and does not alter the amount of flash memory required. Of course, the number
of buffers can affect the application’s performance.