Echelon ISI - Manual (Page 25)

23 ISI Programmer’s Guide
Key advantage Active process—
device is in
control of
proceedings and
aware of success
or failure
Passive process,
supporting resource-
restricted device
implementations
Supports
installation of
replacement or
redundant domain
address servers
Acquiring a Domain Address from a Domain Address
Server
To acquire a domain address from a domain address server, start the ISI engine
using the IsiStartDA() function, or using the IsiStart() function with the
isiTypeDa type.
A domain address server must be in device acquisition mode to respond to
domain ID requests. To start device acquisition mode on a domain address
server, call the IsiStartDeviceAcquisition() function.
To start domain acquisition on a device that supports domain acquisition, call the
IsiAcquireDomain() function.
A typical implementation starts the domain acquisition process when the
Connect button is activated and a domain is not already assigned. If
SharedServicePin is set to FALSE, the IsiAcquireDomain() function also issues a
standard service pin message—this allows using the same installation paradigm
in both a managed and an unmanaged environment. If the application uses the
physical service pin to trigger calls to the IsiAcquireDomain() function, the
system image will have issued a service pin message automatically, and the
SharedServicePin flag should be set to TRUE in this case.
When calling IsiAcquireDomain() with SharedServicePin set to FALSE while the
ISI engine is not running, a standard service pin message is issued nevertheless,
allowing the same installation paradigm and same application code to be used in
both self-installed and the managed networks.
After domain acquisition has been enabled by calling IsiStartDeviceAcquisition()
on the domain address server and it has been started on the device by calling
IsiAcquireDomain(), the device responds to the isiWink ISI event with a visible or
audible response. For example, a device may flash its LEDs. The user confirms
that the correct device executed its wink routine and the DAS application then
confirms the device by calling IsiStartDeviceAcquisition() once again. Once
confirmed, the domain address server grants the unique domain ID to the device.
The device notifies its application with ISI events accordingly.