NetLinx Security within the Web Server
102 NI-3101-SIG Signature Series NetLinx Integrated Controller

What is the difference between Program and Run-time defined binding?

In DDD, the device discovery activity is always dynamic because the devices will always be detected at
run-time. Note that DDD splits the binding activity into two different categories:
Program defined binding (also known as static)
Run-time defined binding (also known as dynamic).
With program defined/static binding, the developer specifies a permanent binding between an
application device and a physical port, such as a particular serial or IR port. At run-time, any device
detected on that port is automatically associated with the designated application device. This binding
type would be used when the developer wants to hard code what port is used for a device, but does not
know what manufacturer's device will actually be connected. Static binding is not available for IP
connected devices, since the IP Address value of a device is subject to change due to IP network
topology.
An example of its use would be if DHCP is enabled for the peripheral device. A
hard-coded IP Address within the NetLinx "glue-code" would be inadequate due to the nature
of the dynamically acquired DHCP IP Addresses. Only actual NetLinx D:P:S values are
allowed for static binding of physical ports.
With run-time defined/dynamic binding, the application device and the physical port are completely
disassociated (in a program sense). The developer defines the application devices and their associated
SDK class but does not specify what physical port they are bound to. At run-time, as those devices are
discovered, the new physical devices are then bound to an application device either automatically or via
the Master's Web access. Dynamic binding is the only binding option available for IP-connected
peripheral devices due to the dynamic nature of IP Addresses as discussed earlier.
Manage Other Devices - Manage Device Bindings
To access this page, click on the Manage Device Bindings button (from within the Manage Other
Device page). This page is used to configure application-defined Duet virtual devices with discovered
physical devices. The on-screen table (FIG.66) di splays a list of all application-defined devices
(including the defined "friendly name"), the Duet virtual D:P:S, and the associated Duet Device SDK
class (indicating the type of the device). This information would have been pre-coded into the NetLinx
file currently on the target Master (FIG.65).