Echelon LonTal Stack - Manual (Page 193)

LonTalk Stack Developer’s Guide 181
Commonly Used LonTalk API Functions
The following table lists API functions that you will most likely use in your
LonTalk Stack application.
Function Description
LonEventPump() Processes any messages received by the LonTalk host stack. If
messages are received, it calls the appropriate event handler
functions.
See Periodically Calling the Event Pump for more information
about this function.
LonExit() Stops the LonTalk host stack for an orderly shutdown of the
LonTalk Stack device.
LonInit() Initializes the LonTalk API and the LonTalk host stack. This
function downloads LonTalk Stack device interface data from the
LonTalk Stack application to the Echelon Smart Transceiver or
Neuron Chip.
The LonTalk Stack application must call LonInit() once on
startup.
LonPropagateNv() Propagates a network variable value to the network.
This function propagates a network variable if all of the following
conditions are met:
• The network variable is declared with the output modifier
• The network variable must be bound to the network
• The network variable must not be declared with the
polled modifier.
Other LonTalk API Functions
The following table lists other LonTalk API functions that you can use in your
LonTalk Stack application. These functions are not typically used by most
LonTalk Stack applications, or are used only for specific application functionality
(for example, including support for changeable-type network variables).
Function Description
LonFreeNvTypeData() Frees internal buffers that were allocated by a call to the
LonQueryNvType() function.
LonGetDeclaredNvSize() Gets the declared size for a network variable.
LonGetNvValue() Gets a pointer to the value for a network variable. This
function is required for dynamic network variables, but could
be used for any network variable.