A communication driver is a DLL containing
specific information about the remote equipment and implements the
communication protocol. Drivers for dozens of common and
not-so-common devices are installed with InduSoft Web Studio.
( InduSoft also provides a toolkit to develop new
communication drivers. For more information, please contact
Customer Support.)
The Drivers task/worksheet allows you to define the
communication interface (or interfaces) between the project and
remote equipment; such as a PLC, a single-loop, and
transmitters.
Note: Consult
the Help menu for a description
of the functions and characteristics that are standard for all
drivers. When developing a project, you can also refer to the
specific documentation provided with each communication driver.
This documentation is usually located in the DRV directory.
To configure a communication driver, you must specify
the interface parameters (for example, the station address and the
baud rate), specify the equipment addresses, and then link them to
project tags.
Use one of the following methods to add or remove a
driver:
- On the Insert tab of the ribbon, in the
Communication group, click Add/Remove
Driver; or
- Right-click the Drivers folder in the Project Explorer, and
then click Add/Remove drivers on
the shortcut menu.
Both methods open a
Communication Drivers dialog, which
displays a list of available drivers.
Figure 1.
Communication Drivers dialog
Use the parameters on this dialog, as follows:
- Available Drivers
field: Lists all available drivers and a brief description of
each.
- Help button: Click
to open the Help menu, which
contains detailed configuration instructions for the driver
currently highlighted in the Available
Drivers field.
- Select button:
Click to select the driver currently highlighted in the
Available Drivers field.
- Selected Drivers
field: Lists all selected drivers and their descriptions (if
available).
- Remove button:
Click to remove a driver currently highlighted in the Selected Drivers field.
When you click OK in
the Communications Driver
dialog, you create a subfolder for the selected driver(s) in the
Drivers folder located on the
Comm tab.
You can right-click on a driver subfolder to access
the
Settings option, which opens
the
Communications Parameters
dialog.
Figure 2. Sample
Communications Parameters dialog
Use the parameters on this dialog, as follows:
- Serial
Encapsulation field: Enables serial drivers to communicate
with modem, TCP/IP or UDP connections. This setting is supported
only for serial drivers developed with the UNICOMM library, which
includes most of the serial drivers available in the product.
CAUTION:
The Modem option is not supported for Pocket PC
v3.00 or older.
Note: This
section covers only the None
option, which enables the driver to connect using a normal serial
channel. Please refer to "Using TCP/IP and UDP Encapsulation" and
"Using Modem Connections" below for more information about other
encapsulation modes. "Serial Encapsulation Tests" below lists the
drivers that have been tested with modem, TCP/IP and UDP
modes.
- COM field: Click
to select a serial communication port.
- Baud Rate,
Data Bits, Stop Bits, and
Parity fields: Click to select parameters for a serial port
configuration.
- Long1,
Long2, String1, and String2 fields: These fields are driver
custom settings. In the example above, the driver uses Long1 to set up the error detection method
and String1 to define the PLC
family type.
- Advanced button:
Click to open the Advanced
settings dialog. Use this dialog to change the default
driver parameters.
Figure 3. Advanced
Settings dialog
Specify or change the default driver parameters as
follows:
The development application provides two interfaces,
which you can use to configure the driver (associating project tags
to device addresses):
-
MAIN DRIVER SHEET: Provides the
easiest method for configuring communication between project tags
and device addresses. This interface allows you to automatically
group tags to provide the best performance during runtime. You
cannot use this interface to control the time needed to scan a
group of tags individually.
-
STANDARD DRIVER SHEETS: Allows
you to control the time needed to scan a group of tags
individually.
You can use both sheets at the same time.
Using TCP/IP and UDP
Encapsulation
Most of the serial drivers allow the use of TCP/IP
or UDP/IP encapsulation. The encapsulation mode has been designed
to provide communication with serial devices connected to terminal
servers on your ethernet or wireless networks. A terminal server
can be seen as a virtual serial port. It converts TCP/IP or UDP/IP
messages on your Ethernet or Wireless network to serial data. Once
the message has been converted to a serial form, you can connect
standard devices that support serial communications to the terminal
server. The following diagram provides one example of applying this
solution:
Figure 4. TCP/IP
Encapsulation
You can enable the encapsulation by following the
steps below:
- Right-click on the driver's folder, and then choose
Settings from the shortcut menu.
This will give you access to the communication
parameters.
- In the Serial
Encapsulation field, select TCP/IP or UDP/IP:
The following fields are available:
- IP Address field:
Specify the IP Address for the Terminal Server. This field accepts
tags in curly brackets.
- Port Number field:
Enter the TCP/IP or UDP/IP port number.
- Status Tag field:
This field is available only when using TCP/IP. The tag on this
field receives the value 1 when the TCP/IP connection is
established; otherwise, it receives 0.
- Server Mode field:
The TCP/IP encapsulation allows the Server Mode, making the remote
client responsible for establishing the connection to enable the
communication.
Using Modem Connections
Most of the serial drivers allow the use of modem
connections. The modem connection has been designed to enable
communications with remote serial devices connected through a phone
line. The following diagram provides one example of applying this
solution:
Figure 5. Modem
Connection
You can enable the modem connection by following the
steps below:
- Right-click on the driver's folder, and then choose
Settings from the shortcut menu.
This will give you access to the communication
parameters.
- In the Serial
Encapsulation menu, select Modem:
CAUTION:
The Modem option is not supported for Pocket PC
v3.00 or older.
The following fields are available:
- Name drop-down
list: Select the modem that the driver will use to establish the
connection. If you do not know the modem name, use the Auto Detect
option. The Auto Detect 1 will
use the first modem available, Auto
Detect 2 will use the second, Auto Detect 3 will use the third, and
Auto Detect 4 will use the
fourth.
- Phone field: Enter
a phone number that the driver will use to connect to the remote
device. This field accepts tags between curly brackets.
- Settings button:
Click on this button to configure the modem settings. The window
that displays when you click on this button depends on the
operating system that you are using and on the modem type.
CAUTION:
The settings configured by clicking on
this button are not saved with your project. The information is
saved on the operating system registry, and they are valid only in
the computer that you are interacting with. If you install your
project on another computer, you will have to reconfigure these
settings.
- Connection button:
Click to open the Connection
Control window. The default connection settings should
suffice for most of the projects. However, you can take full
control over the connection, and also enable incoming calls, by
clicking on this button.
Figure 6. Connection
Control dialog
- Dial out trigger
field: When the value of the tag configured in this field changes,
the driver will try to connect to the remote device. If the
connection has already been established, the command is ignored.
You do not have to use this field if you are using Auto
Connect.
- Hang up trigger
field: When the value of the tag configured in this field changes,
the driver will disconnect from the remote device. If the device is
disconnected the command is ignored. You do not have to use this
field if you are using Disconnect call if idle for more than.
- Auto Connect
field: When this option is enabled, the driver will try to connect
to the remote device before sending any information. If the
connection fails, the next attempt will be made after the Retry
Interval has expired.
- Disconnect call if idle
for more than field: When this option is checked, the driver
will automatically disconnect from the remote device if no
communication is performed after the time you specified.
- Enable incoming
calls field: Check this option if you want to enable the
driver to receive calls from the remote device. You can use the
Hang up trigger to drop the call once it has been established.
Notice that one driver can use both incoming calls and outgoing
calls.
- Status area
- Code field: Enter
with a tag that will receive one of the following codes when the
driver is running:
- 0 = Disconnected
- 1 = Connected
- 2 = Dialing
- 3 = Dropping
- 4 = Closing Line
- Description field:
Enter with a tag that will receive a complete description of the
current status. The description is associated with the Code field; however, it brings some
additional information about the current status.
Serial Encapsulation Tests
Most of the serial drivers should work with every
serial encapsulation mode. However, most of the drivers were
developed before the encapsulation modes had been created. The
following table lists the drivers fully tested with certain
encapsulation modes; if the driver that you intend to use is not
listed and you are unsure whether it will work, please contact your
distributor.
Driver |
Modem |
TCP/IP |
UDP/IP |
MODSL |
X |
X |
X |
ABKE |
X |
X |
X |
MODBU |
X |
|
X |
OMETH |
X |
|
|
X = Item has been
tested