User manual

Klinkmann Automation SPA Bus Server 18
SPA Server Ver 1.x User Manual Rev 2.3 120XXM23
Item Names
The SPA Server uses an item/point naming convention, based on the format of SPA bus
master messages. The SPA Server item names also must fit inside the range of data
categories and bus codes defined in the SPA Server Unit Definition File (see SPA Server
Unit Definition File section below) for the appropriate unit (device). The Unit Definition
File is read at SPA Server start-up and all item names are checked for correspondence
with data defined in the Unit Definition File, i.e. if item does not match with information
included in the Unit Definition File then item is rejected even if the item name syntax is
correct.
The item names used in the SPA Server generally may be described as:
DTc.m:p
where:
D -- Data category. Possible values for data category can be:
I, i -- Input
O, o -- Output
S, s -- Setting
V, v -- Variable
M, m -- Memory
T – Data Type of item. Possible values can be:
D, d -- Discrete, values: 0, 1;
I, i -- Integer, value range: --2147483648 ... [phone];
R, r -- Real, value range: --9999999999. 9999999999 ...
+9999999999.9999999999;
M, m -- Message, maximal length 131 bytes, can contain ASCII characters
(from 0x20 to 0x7E) except CR (0x0D), LF (0x0A), ">", "<", ":", "/" and
"&";
c -- channel number, value can be 0 ... 999;
m -- data number, value can be 1 ... 999999;
:p -- optionally suffix to indicate the precision of data for write commands. The p value
can be from 0 to 10 and if item name does not contain the suffix :p then default value is 2
for Real items and 0 for Integer items. All unnecessared 0-digits and decimal point will be
removed from write command. If necessary the data value will be rounded.
For Reals the precision is the number of digits after decimal point, e.g., if value to write is
123.123456 and precision is :4 then the write command will contain the value 123.1235. If
value to write is 0.01034 and precision is :3 then the write command will contain the value
0.01 and if precision is :0 then only integer part of value will be written.
For Integers the precision can be used if the number of leading zeroes has some
importance for the slave. In this case the precision is the number of data value digits in
the write command including leading zeroes, e.g., if value to write is 123 and precision is
:5 then the write command will contain the value 00123. The precision is effective only for
positive (value equal or greater than zero) integer values.