Software
Manual SCA-340 / SCA-340-L
sysmik.de
37
4.4
Real-Time Control with Scalibur and Sedona
Sedona allows to program control applications, which run with configurable cycle
times. Sedona must first be activated from the SCA system shell (s. 4.1.1) or the
commissioning website (s. 4.1.2). Niagara Workbench is used as engineering tool.
The programming follows a component-based approach: The application consists of
components, which are parameterized and connected with each other. With the
textual programming language Sedona (similar to C++ and Java), it is even possible
to create own Sedona components. An introduction to Sedona offers [4], while
further, more detailed information can be found in [6].
4.4.1
IO Access
Hardware data points can be accessed via the terminal components of the
SysMikScaIo
kit. There is a component for each terminal type with its specific slots,
that allow to access inputs and outputs and to parameterize the terminal.
The component
ScaIo
works as folder, into which the hardware related components
are added. Furthermore, it provides an Action
Restart IO
to restart the IO server.
Each terminal component has a property
Terminal
, which defines the terminal
position. The first terminal directly at the Scalibur has position 1, and so on. Some
terminal components contain further parameters (e.g. measuring ranges for analog
input terminals) or actions (e.g. counter initialization of pulse metering terminals).
Table 4.4.1:
PropertySheet view of a terminal component
4.4.2
Modbus
Via
Platform Service
, a Modbus TCP server can be started for the Sedona Virtual
Machine, which hosts the following data points:
10,000 coils (digital outputs)
10,000 discrete inputs (digital inputs)
10,000 holding registers (analog outputs)
10,000 input registers (analog inputs)
The Sedona application has access to these data points via components of the kit
SysMikModbusServer
.
Additionally, with components of the kit
SysMikModbusClient
, the Sedona
application can act as Modbus TCP client or Modbus RTU master to read and write
data points of remote Modbus devices.