User Manual

30
Siemens Building Technologies
Cerberus Division
e1143b
06.2000
4.5 FHI Pad Technological points image
FHI Pad maintains an image of all technological points to be transmitted to the LMS
using a technological point table. This table contains the correlation between the FSS
block representation and the CMX points that represent technological points inside
LMS.
When a change of status occurs in the technological field devices, the FSS issues a
Standard Protocol message to the FHI Pad.
The FHI Pad firmware looks at the technological point table and accesses it through the
Block number values.
The table is dimensioned for the maximum number of technological points declared in
"Configuration limits" chapter. The table holds the image of both input points (DI/AI) and
output blocks (DO/AO).
The technological point table links the technological block and the virtual LMS point that
it represents. The point status is changed according to the CDSF message received
and this change of status is notified to the LMS. In order to do that, FHI Pad will use the
Standard Message, according to the following message structure:
Standard message LMS level FSS level
0 00H 00H
1 year year
2 month month
3 day day
4 hour hour
5 minute minute
6 seconds seconds
7-8 local address 0000H
9-10 point number block number
11 treatment flag treatment flag
byte
12-15 point value point value
4.6 Image initialisation
If the connection with FSS is interrupted, i.e. if the FHI Pad detects a line down status,
FHI Pad sends a message to LMS to set point # 1 of all the CMX units to 1 (Connection
to the gateway down).
The FHI Pad will send a message to the LMS to set point #1 to 0 ( i.e. connection to the
gateway on) only after the first scan cycle is totally completed. The line up condition will
cause a status request to be generated by the LMS, which will be transmitted via the
FHI Pad to the FSS. It is up to FSS to answer with all the point values which are differ-
ent from the default values.