FNM alpha SM 230, User Manual, Page: 59 / 72

58 59
Operation
Login procedure PC at the base module
The base module has the possibility to buffer received data sets in case of temporary
switching off of the PC. A registration of the PC at the base module is necessary to
control this mechanism.
After activating the base module, it sends the message "SERVICE_MSG_MODULE_
LOGIN_IND". This has to be acknowledged in every case. For this purpose, the PC
sends the message „SERVICE_MSG_PC_LOGIN_REQ“.
In case the base station has already been activated when the application software
is started, the message "SERVICE_MSG_PC_LOGIN_REQ" will also have to be sent
from the PC. The base module acknowledges the message and gives an information
whether stored data exists. These data can now be recalled and deleted.
After successful login, the base module now outputs all data sets over the interface to
the PC.
The base module waits for a message from the PC for the connection control every
5 minutes during operation. This message should occur at the latest after 5 minutes,
but at the earliest a few seconds before.
In case this message is missing, the base module automatically starts to store the re-
ceived data sets. In case the connection is established again, the base module then
gives the PC an information that the data was stored.
In case the application software should be closed shortly, the PC releases a logout
message. The base module acknowledges this message and stores the received
data sets from then on until the new login of the PC.
Please bear in mind that only a limited number of data sets can be buffered!