Instruction Manual

74 Developing an FTXL Application
Overview of an FTXL Application
This chapter describes how to use the FTXL LonTalk API and the application
framework produced by the LonTalk Interface Developer utility to perform the
following tasks:
• Use the FTXL LonTalk API and FTXL LonTalk protocol stack
• Integrate the application with an operating system
• Provide persistent storage for non-volatile data
• Initialize the FTXL device
• Periodically call the FTXL event pump
• Send information to other devices using network variables
• Receive information from other devices using network variables
• Handle network variable poll requests from other devices
• Handle updates to changeable-type network variables
• Handle dynamic network variables
• Communicate with other devices using application messages
• Handle management tasks and events
• Handle local network management commands
• Handle reset events
• Query the error log
• Use the direct memory files feature
• Shut down the FTXL device
Most FTXL applications need to perform only the tasks that relate to persistent
storage, initialization, calling the event pump, and sending and receiving
network variables.
This chapter shows you the basic control flow for each of the above tasks. It also
provides a simple code example to illustrate some of the basic tasks.
Using the FTXL LonTalk API
Within the seven-layer OSI Model protocol, the FTXL LonTalk API forms the
majority of the Presentation layer, and provides the interface between the FTXL
LonTalk protocol stack in the Session layer and the host application in the
Application layer, as shown in
Figure 9 on page 75.