User manual

Klinkmann Automation SPA Bus Server 20
SPA Server Ver 1.x User Manual Rev 2.3 120XXM23
The ITEMCOUNT item is an Integer type Read Only item used to access the number of
active items in the corresponding topic. The range of valid values is from 0 to
2147483647.
ERRORCOUNT
The ERRORCOUNT item is an Integer type Read Only item used to access the number
of active items with errors in the corresponding topic. The range of valid values is from 0
to 2147483647.
ERRORITEMS
The ERRORITEMS item is an Integer type Read/Write Only (unique for each topic) used
to access the total number of items with invalid item names (these items are rejected by
Server) and items with valid names but with non-existing address in SPA device. The
ERRORITEMS value can be reseted by writing 0 to this item. The range of valid values is
from 0 to 2147483647.
WRITECOUNT
The WRITECOUNT item is an Integer type Read Only item used to access the number of
write commands (messages) waiting for execution. The range of valid values is from 0 to
2147483647.
For example, in following way the WRITECOUNT item can be used to avoid the
increasing of memory occupied by not executed write commands:
- activate the hot link with WRITECOUNT item and start to monitor it;
- activate new write command (by poking new value) only if value of WRITECOUNT
becomes equal to 0, e.g., all previous write commands are executed and memory
occupied by them is freed.
SUSPEND
Special Read/Write Discrete Item SUSPEND may be used to control the communication
with a separate topic. If application changes SUSPEND value from 0 to 1 then
communication with topic is suspended. If SUSPEND value is changed back to 0 then
communication with this topic is resumed.
Note: If topic is suspended by setting SUSPEND value to 1, then Server rejects all new
write values to this topic, i.e., no new write messages are created after SUSPEND value
has changed from 0 to 1.
Item/Point Naming Examples
The following examples show the valid item names:
ID0.1 -- Discrete input 1, channel 0;
OR6.90 -- Real output 90, channel 6;
SD999.5 -- Discrete setting 5, channel 999;
SR1.5:3 -- Real setting 5, channel 1, precision 3;
VI455.999999 -- Integer variable 999999, channel 455;
MM85.154-- Message type memory item 154, channel 85;
F -- Slave identification code;
A0 -- Alarms from channel 0;
STATUS -- Communication status.