CoDeSys V3 - Quick Start 6/6

Testing the Application

Now that we have programmed our complete garage door application we need to do some testing to make sure that everything functions correctly. Yet, as we do not have a real garage door drive at hand with all the sensors and actuators required we have to simulate them manually. CoDeSys offers a completely integrated and comprehensive debugging functionality which will help us test our application.

First of all we have to log in to the controller and download the code created by our application. During this process, CoDeSys turns the graphical FBD code into real machine code using its integrated compilers, which support all kinds of different CPUs and OS platforms. Our device is the SoftPLC on our PC which we configured in the project configuration before we started to program our application (see unit 2). Of course, we can later operate our application on any desired device/controller programmable with CoDeSys.

We get logged in to the controller with the command ‘Login to Application [name]’ from the menu ‘Online’. CoDeSys now checks whether an application is already running on our target device (SoftPLC) and if so, which application this is. A dialogue window with the text: “Application does not exist on device. Do you want to create it and proceed with download?” appears upon the first download.

If we confirm this window, CoDeSys compiles the programmed application code and starts to download it to the device. What is currently happening and the state of progress is displayed in the status bar on the bottom left-hand side.

As soon as the download is complete the following happens:

The red ‘STOP’ in the status bar also shows that the application has not yet been started and the message ‘Program loaded’ is displayed.

If it is not possible to establish an online connection as shown above, we have to check the communication settings described at the end of the Configuration of the project .

Should we have made syntactical errors in our application code so that it cannot be compiled, CoDeSys will issue the following message: “There are compile errors. Do you want to login without download?“

This message box is closed by clicking on the ‘No’ button and we can then try to fix the error or errors. All errors detected by CoDeSys and their location are listed in the message window (usually located in the lower part of our screen). The best thing to do is to go through the errors (or messages) listed step by step. If we press the ”F4” key, CoDeSys jumps from one message to the next and displays the erroneous lines in the application code.



We can now thoroughly check the erroneous code parts and correct them. A typical error would be for example an FBD block with an open, unassigned input pin. Once we have corrected a detected error, we can jump to the next one by pressing ”F4”.

After fixing all errors detected we can test our application by pressing the ”F11”key. The application is compiled but the native code not yet downloaded on to the controller. If no further errors are found the following message appears in the message window:

“Compile complete -- 0 errors, 0 warnings”.

With ‘Login to Application [name]’ from the menu ‘Online’ or by pressing the button in the tool bar we can log in to the controller again. And then, in order to be able to test the application, we have to start it by pressing the “F5“ key or via the menu ‘Online/Start Application [Device: PLC Logic]’. The word [run] now appears in brackets behind the application in the device tree and in capital letters in the bottom status bar (RUN). In the application code, i.e. in the POU PLC_PRG all Boolean variables are set FALSE. Only the blinking signal for the error monitoring in the last network changes from TRUE to FALSE every second.

In order to be able to test the functionality of our application we have to change the global variables set in the Declaration of the variables : Actuation and the sensors DoorOpen, DoorClosed and DriveOverload. This can be done in our variable list ’SimulationSignals’ from where we can directly operate the application.

By clicking in the column ‘Prepared value’ we can change the Boolean variable.

Attention:
Such a prepared value has not yet been written onto the controller! It could well be possible that several values have to be changed simultaneously within one controller cycle to avoid damage to the machine or in the process. That is why the command ‘Online/Write Values’ (shortcut “Ctrl + F7”) has to be executed in order to write our value Actuation.

Once Actuation has been written the garage door will start to close because all variable values of the application were set FALSE or 0 after the first download (if no other initial values were defined in the declaration).




As the garage door is closing the value of DoorDown is set TRUE by the application. The same applies for our lighting and its variable Lighting. Just as desired the light goes on when the garage door is in operation.

In order to be able to follow every single step programmed, we now have to manually reset Actuation to FALSE and then simulate the sensor DoorClosed by setting it to TRUE (and then back to FALSE). The actuator DoorDown is then set FALSE by the application and the door is closed. After 10 seconds the light is automatically turned off and the variable Lighting is set FALSE.

By once more pressing the control button, i.e. by setting the variable Actuation TRUE we can test the opening procedure of the gate. The variables involved are now the variables needed for opening the gate DoorUp and DoorOpen.

If we do not manually end the opening or closing procedure by simulating the sensor variables DoorClosed or DoorOpen, the application recognizes an error after the predefined time of 20 seconds, allowed for these procedures, has elapsed. As a consequence, the actuator DoorDown or DoorUp is set FALSE and the light starts to blink and the variable Lighting changes from TRUE to FALSE. By once more pressing the control button (Actuation is set TRUE) the error is acknowledged, the light stops blinking and we have returned to our initial state. The error DriveOverload can be tested by manually setting it TRUE while the gate is opening or closing. Again the garage door is stopped and the error is signalled by the blinking light.

Download the complete application as a CoDeSys V3 project archive

A CoDeSys V3 project archive can be opened in CoDeSys V3 using the menu command “File/Project Archive/Extract Archive…”.

Please note:
Our sample application can only be executed in CoDeSys V3.3 (or higher).