View source for OpenPLC-with-LDmicro/C2/Negated-Coil-and-Negated-Contact/English


{| style="border-spacing:0;"
| style="border:1pt solid #000000;padding:0.176cm;"| <center>'''Visual Cue'''</center>
| style="border:1pt solid #000000;padding:0.176cm;"| <center>'''Narration'''</center>

|-
| style="border:1pt solid #000000;padding:0.176cm;"| Slide 1: 
| style="border:1pt solid #000000;padding:0.176cm;"| Welcome to the spoken tutorial on''' Negated Coil & Negated Contact.'''

|-
| style="border:1pt solid #000000;padding:0.176cm;"| Slide 2: Learning Objectives:

* Negated Coil
* Negated Contact

| style="border:1pt solid #000000;padding:0.176cm;"| In this tutorial, we will learn about working of

* '''Negated Coil'''
* '''Negated Contact'''
|-
| style="border:1pt solid #000000;padding:0.176cm;"| Slide 3: System Requirements

* '''Ubuntu Linux''' 18.04 OS
* '''LDmicro'''
* '''OpenPLC''' '''Mainboard'''
* 24V, 2A '''SMPS'''
* '''USBasp programmer'''
* '''Traffic Light module'''
* '''Switchboard module'''

| style="border:1pt solid #000000;padding:0.176cm;"| To record this tutorial I am using:

* '''Ubuntu Linux 18.04''' operating system
* '''LDmicro'''
* '''OpenPLC Mainboard'''
* '''24V, 2A SMPS'''
* '''USBasp''' programmer
* '''Traffic Light''' module
* '''Switchboard''' module

|-
| style="border:1pt solid #000000;padding:0.176cm;"| Slide 4: Pre-requisites

* Program OpenPLC Mainboard and
* Interface OpenPLC modules with Mainboard. 

If not, please refer to the relevant tutorials from [https://spoken-tutorial.org/ Home | spoken-tutorial.org]
| style="border:1pt solid #000000;padding:0.176cm;"| 
* To follow this tutorial, you should know how to 
*# program '''OpenPLC Mainboard''' and
*# interface '''OpenPLC''' modules with '''Mainboard'''. 
* If not, please refer to the relevant tutorials in this series on this website.

|-
| style="border:1pt solid #000000;padding:0.176cm;"| Slide 5: Prerequisites - Hardware setup

| style="border:1pt solid #000000;padding:0.176cm;"| Connect''' SMPS''' and '''USBasp''' to the '''Mainboard''' as shown in the picture.

Keep these connections throughout this tutorial.

|-
| style="border:1pt solid #000000;padding:0.176cm;"| Open LDmicro 
| style="border:1pt solid #000000;padding:0.176cm;"| Let us open '''LDmicro'''.

|-
| style="border:1pt solid #000000;padding:0.176cm;"| 
| style="border:1pt solid #000000;padding:0.176cm;"| First, we’ll learn about working of a '''Negated Coil'''.

|-
| style="border:1pt solid #000000;padding:0.176cm;"| Click ‘Instructions -> Insert Coil’
| style="border:1pt solid #000000;padding:0.176cm;"| Insert a '''Coil''' from '''Instructions''' as shown.

|-
| style="border:1pt solid #000000;padding:0.176cm;"| Double-click on the coil
| style="border:1pt solid #000000;padding:0.176cm;"| Double-click on the '''Coil'''.

|-
| style="border:1pt solid #000000;padding:0.176cm;"| Click ‘Negated’ radio button >> Type LED in the name column

Click OK button
| style="border:1pt solid #000000;padding:0.176cm;"| Select the ‘'''Negated'''’ option in the '''Type''' column. 

Rename the '''Coil''' as '''LED''' and click on the '''OK''' button.

|-
| style="border:1pt solid #000000;padding:0.176cm;"| Highlight coil
| style="border:1pt solid #000000;padding:0.176cm;"| We can observe a '''slash''' between the brackets for a '''Negated Coil'''.

|-
| style="border:1pt solid #000000;padding:0.176cm;"| 
| style="border:1pt solid #000000;padding:0.176cm;"| We will now check the working of this '''logic'''.

|-
| style="border:1pt solid #000000;padding:0.176cm;"| Click ‘Simulate -> Simulation mode’

Click ‘Simulate -> Real-time simulation’
| style="border:1pt solid #000000;padding:0.176cm;"| Let us turn on the '''Simulation mode'''.

For that, click '''Simulate''' and then on '''Simulation mode.'''

Next, start real-time '''simulation''' as shown.

|-
| style="border:1pt solid #000000;padding:0.176cm;"| Highlight I/O list
| style="border:1pt solid #000000;padding:0.176cm;"| Observe the state of '''YLED''' in the '''I/O list.'''

|-
| style="border:1pt solid #000000;padding:0.176cm;"| Highlight the state of YLED in I/O list at the bottom of the screen
| style="border:1pt solid #000000;padding:0.176cm;"| We can observe that the state of '''YLED''' is 0.

That is for a '''Negated Coil''' when the '''input''' is '''logic''' 1, the '''output''' will be '''logic''' 0.

|-
| style="border:1pt solid #000000;padding:0.176cm;"| Click Simulate -> Halt Simulation >> Click Simulate -> Simulation Mode
| style="border:1pt solid #000000;padding:0.176cm;"| Now, turn off the '''Simulation mode'''.

For that, click '''Simulate''' and then on '''Halt Simulation.'''

Then click '''Simulate''' and '''Simulation Mode.'''

|-
| style="border:1pt solid #000000;padding:0.176cm;"| Narration only
| style="border:1pt solid #000000;padding:0.176cm;"| Now let us '''compile''' the '''logic'''.

The detailed steps on how to '''compile''' and save the '''logic''' are explained in the earlier tutorials. 

|-
| style="border:1pt solid #000000;padding:0.176cm;"| Click on Settings >> Click on Microcontroller >> Select AVR ATmega16 40-PDIP 

Click on Settings >> Click on MCU parameters >> Change Crystal frequency to 16
| style="border:1pt solid #000000;padding:0.176cm;"| Click on '''Settings''' and select the '''micro-controller AVR ATmega16 40-PDIP.''' 

Adjust its '''parameters''' as shown here.

|-
| style="border:1pt solid #000000;padding:0.176cm;"| Double-click on YLED in I/O list >> Select PA0 >> Click OK button
| style="border:1pt solid #000000;padding:0.176cm;"| Then, assign '''pin PA0''' to the '''Coil YLED'''.

|-
| style="border:1pt solid #000000;padding:0.176cm;"| Click on Compile >> Click on Compile >> Go to Desktop/LDmicro folder >> Rename it as ‘negatedcoil.hex’ >> Click on Save.

Click OK button
| style="border:1pt solid #000000;padding:0.176cm;"| '''Compile''' the '''logic''' as '''negatedcoil.hex''' as shown.

|-
| style="border:1pt solid #000000;padding:0.176cm;"| Click on File >> Click on Save >> Go to Desktop/LDmicro folder >> Rename it as ‘negatedcoil.ld’ >> Click on Save
| style="border:1pt solid #000000;padding:0.176cm;"| Then save the '''ladder diagram''' as '''negatedcoil.ld''' as shown.

|-
| style="border:1pt solid #000000;padding:0.176cm;"| 
| style="border:1pt solid #000000;padding:0.176cm;"| Now we will see the working of this '''logic''' on hardware.

|-
| style="border:1pt solid #000000;padding:0.176cm;"| Connect Mainboard to PC using USBasp

| style="border:1pt solid #000000;padding:0.176cm;"| Connect the '''Mainboard''' to your laptop using '''USBasp'''.

Turn on the '''power supply'''.

|-
| style="border:1pt solid #000000;padding:0.176cm;"| Open terminal >> Type cd Desktop/LDmicro >> Press ENTER >> type ‘'''avrdude -c usbasp -p m16 -U flash:w:negatedcoil.hex’ '''>> Press ENTER
| style="border:1pt solid #000000;padding:0.176cm;"| Open the '''terminal''' by pressing '''CTRL+ALT+T''' keys simultaneously.

Go to the folder where you have saved the '''hex file'''.

Type the '''command''' as shown to upload the '''hex file''' to the '''Mainboard'''.

|-
| style="border:1pt solid #000000;padding:0.176cm;"| Remove the '''USBasp''' connection from the laptop.
| style="border:1pt solid #000000;padding:0.176cm;"| Turn off the '''power supply'''.

Remove the '''USBasp connection''' from the laptop.

This will prevent any hardware damage.

|-
| style="border:1pt solid #000000;padding:0.176cm;"| 
| style="border:1pt solid #000000;padding:0.176cm;"| Let us see the connection details now. 

|-
| style="border:1pt solid #000000;padding:0.176cm;"| Show the connections as per the narration
| style="border:1pt solid #000000;padding:0.176cm;"| Connect '''+5V pin''' of the red '''LED''' of '''Traffic Light module''' to '''5V pin''' of the '''Mainboard'''.

Then connect the '''GND pin''' of the red '''LED''' to '''PA0 pin''' of the '''Mainboard'''.

Make the connections as shown in the picture.

|-
| style="border:1pt solid #000000;padding:0.176cm;"| Point as per the narration
| style="border:1pt solid #000000;padding:0.176cm;"| Note the difference in the connections with that of a '''Normal Coil'''.

|-
| style="border:1pt solid #000000;padding:0.176cm;"| Turn on the power
| style="border:1pt solid #000000;padding:0.176cm;"| After making all the connections properly turn on the '''power supply'''.

|-
| style="border:1pt solid #000000;padding:0.176cm;"| Point to the output

| style="border:1pt solid #000000;padding:0.176cm;"| We can observe that the red '''LED''' is glowing.

That is the '''I/O pin PA0''' gives the '''output''' of the '''Coil''' which is '''logic''' 0.

|-
| style="border:1pt solid #000000;padding:0.176cm;"| 
| style="border:1pt solid #000000;padding:0.176cm;"| Thus we learnt the working of a '''Negated Coil''' using an '''LED'''.

|-
| style="border:1pt solid #000000;padding:0.176cm;"| Turn off the power
| style="border:1pt solid #000000;padding:0.176cm;"| Turn off the '''power supply'''.

Remove the connections made for this example.

|-
| style="border:1pt solid #000000;padding:0.176cm;"| 
| style="border:1pt solid #000000;padding:0.176cm;"| Next, we will learn about the working of '''Negated Contact.'''

|-
| style="border:1pt solid #000000;padding:0.176cm;"| Switch back to LDmicro
| style="border:1pt solid #000000;padding:0.176cm;"| Switch back to '''LDmicro'''.

|-
| style="border:1pt solid #000000;padding:0.176cm;"| Narration only
| style="border:1pt solid #000000;padding:0.176cm;"| Instead of creating a new file, we will make changes in the previous file itself.

|-
| style="border:1pt solid #000000;padding:0.176cm;"| Place the cursor to the left of the coil >> Click on Instruction -> Insert Contact
| style="border:1pt solid #000000;padding:0.176cm;"| Place a '''Contact''' to the left of the '''Coil''' as shown here.

|-
| style="border:1pt solid #000000;padding:0.176cm;"| Double-click on the Contact >> Check the ‘Negated' box
| style="border:1pt solid #000000;padding:0.176cm;"| Double-click on the '''Contact''' and check the '''Negated''' box.

|-
| style="border:1pt solid #000000;padding:0.176cm;"| Narration only
| style="border:1pt solid #000000;padding:0.176cm;"| '''Negated Contact''' will pass the state of the '''signal''' when its state is '''logic''' 0.

|-
| style="border:1pt solid #000000;padding:0.176cm;"| Type switch in the name box >> Click the OK button
| style="border:1pt solid #000000;padding:0.176cm;"| Rename the Contact as '''‘switch’''' and click the OK button.

|-
| style="border:1pt solid #000000;padding:0.176cm;"| 
| style="border:1pt solid #000000;padding:0.176cm;"| We will now check the working of this '''logic'''.

|-
| style="border:1pt solid #000000;padding:0.176cm;"| Click Simulate -> Simulation mode >> Click Simulate -> Real-time simulation
| style="border:1pt solid #000000;padding:0.176cm;"| Start real-time '''simulation''' as shown.

|-
| style="border:1pt solid #000000;padding:0.176cm;"| Highlight the states of both Xswitch and YLED in the I/O list
| style="border:1pt solid #000000;padding:0.176cm;"| Observe the state of the '''Contact''' and the '''Coil''' in the '''I/O list'''.

Initially the state of both '''Xswitch''' and '''YLED''' are 0.

|-
| style="border:1pt solid #000000;padding:0.176cm;"| Double-click on Xswitch
| style="border:1pt solid #000000;padding:0.176cm;"| Change the state of the '''Xswitch''' to 1.

|-
| style="border:1pt solid #000000;padding:0.176cm;"| Highlight the states of both Xswitch and YLED in the I/O list
| style="border:1pt solid #000000;padding:0.176cm;"| We can observe that the state of '''YLED''' is also 1.

|-
| style="border:1pt solid #000000;padding:0.176cm;"| Show the connections as per the narration
| style="border:1pt solid #000000;padding:0.176cm;"| Thus, when the state of a '''Negated Contact''' is 1 it doesn’t pass the signal through it.

That is the '''output''' from a '''Negated Contact''' is 0, when its '''input''' is '''logic''' 1.

|-
| style="border:1pt solid #000000;padding:0.176cm;"| Click Simulate -> Halt Simulation >> Click Simulate -> Simulation Mode
| style="border:1pt solid #000000;padding:0.176cm;"| Turn off the '''simulation mode''' as shown.

|-
| style="border:1pt solid #000000;padding:0.176cm;"| 
| style="border:1pt solid #000000;padding:0.176cm;"| We will now '''compile''' this '''logic'''.

|-
| style="border:1pt solid #000000;padding:0.176cm;"| Highlight the status bar at the bottom of the screen
| style="border:1pt solid #000000;padding:0.176cm;"| We can observe that the '''microcontroller''' and its '''parameters''' are already set.

|-
| style="border:1pt solid #000000;padding:0.176cm;"| Double-click on Xswitch in I/O list >> Select PC0 >> Click OK button
| style="border:1pt solid #000000;padding:0.176cm;"| Assign the '''pin PC0''' to '''Xswitch'''.

|-
| style="border:1pt solid #000000;padding:0.176cm;"| Click on Compile >> Click on Compile as >> Go to Desktop/LDmicro folder >> Rename it as ‘negatedcontact.hex’ >> Click on Save.

Click OK button
| style="border:1pt solid #000000;padding:0.176cm;"| '''Compile''' the '''logic''' as '''negatedcontact.hex '''using the '''‘Compile As’''' option. 

|-
| style="border:1pt solid #000000;padding:0.176cm;"| Click on File >> Click on Save As >> Go to Desktop/LDmicro folder >> Rename it as ‘negated-contact.ld’ >> Click on Save
| style="border:1pt solid #000000;padding:0.176cm;"| Then save the '''ladder diagram''' as '''negatedcontact.ld '''using the '''‘Save As’''' option.

|-
| style="border:1pt solid #000000;padding:0.176cm;"| 
| style="border:1pt solid #000000;padding:0.176cm;"| Now we will see the working of this '''logic''' on hardware.

|-
| style="border:1pt solid #000000;padding:0.176cm;"| Connect Mainboard to PC using USBasp

| style="border:1pt solid #000000;padding:0.176cm;"| Connect the '''Mainboard''' to your laptop using '''USBasp'''.

Turn on the '''power supply'''.

|-
| style="border:1pt solid #000000;padding:0.176cm;"| Switch back to terminal >> type ‘'''avrdude -c usbasp -p m16 -U flash:w:negatedcontact.hex’ '''>> Press ENTER
| style="border:1pt solid #000000;padding:0.176cm;"| Switch back to the '''terminal'''.

Go to the folder where you have saved the '''hex file'''.

Type the '''command''' as shown and upload this '''hex file''' to the '''Mainboard'''.

|-
| style="border:1pt solid #000000;padding:0.176cm;"| Remove the '''USBasp''' connection from the laptop.
| style="border:1pt solid #000000;padding:0.176cm;"| Turn off the '''power supply'''.

Remove the '''USBasp''' connection from the laptop.

This will prevent any hardware damage.

|-
| style="border:1pt solid #000000;padding:0.176cm;"| 
| style="border:1pt solid #000000;padding:0.176cm;"| Let us see the connection details now. 

|-
| style="border:1pt solid #000000;padding:0.176cm;"| Show the connections as per the narration
| style="border:1pt solid #000000;padding:0.176cm;"| Connect '''GND''' and '''5V''' of switchboard to '''GND''' and '''5V''' of the '''Mainboard''' respectively.

Then connect '''NO1''' of the '''switchboard''' to '''PC0''' of the '''Mainboard.'''

|-
| style="border:1pt solid #000000;padding:0.176cm;"|Show the connections as per the narration
| style="border:1pt solid #000000;padding:0.176cm;"| Connect '''+5V pin''' of the red LED of '''Traffic Light module''' to '''5V pin''' of the '''Mainboard'''.

Then connect the '''GND pin''' of the red '''LED''' to '''PA0 pin''' of the '''Mainboard'''.

Make the connections as shown in the picture.

|-
| style="border:1pt solid #000000;padding:0.176cm;"|Turn on the power 
| style="border:1pt solid #000000;padding:0.176cm;"| After making all the connections properly, turn on the '''power supply'''.

|-
| style="border:1pt solid #000000;padding:0.176cm;"| Point as per narration
| style="border:1pt solid #000000;padding:0.176cm;"| We can observe that the '''LED''' glows even before the switch '''NO1''' is pressed.

The red '''LED''' turns off whenever the '''NO1''' is pressed.

That is the corresponding switch '''LED''' and the red '''LED''' glows alternately.

|-
| style="border:1pt solid #000000;padding:0.176cm;"| Show the connections as per the narration
| style="border:1pt solid #000000;padding:0.176cm;"| Now connect '''PC0''' to '''NC1''' instead of '''NO1 '''as shown in the picture.

|-
| style="border:1pt solid #000000;padding:0.176cm;"| Point as per narration
| style="border:1pt solid #000000;padding:0.176cm;"| Let us see the live demo now.

We can observe the red '''LED''' is off initially.

It is ON whenever the switch''' NC1''' is pressed.

That is the corresponding switch '''LED''' and the red '''LED''' glows simultaneously.

|-
| style="border:1pt solid #000000;padding:0.176cm;"| Show the connections as per the narration
| style="border:1pt solid #000000;padding:0.176cm;"| Now connect '''PC0''' to '''L1 '''as shown in the picture.

|-
| style="border:1pt solid #000000;padding:0.176cm;"| Point as per narration
| style="border:1pt solid #000000;padding:0.176cm;"| Initially, the red '''LED''' is on.

The red '''LED''' turns off when the '''L1''' is pressed.

Thus the corresponding switch '''LED''' and the red '''LED''' glows alternately.

|-
| style="border:1pt solid #000000;padding:0.176cm;"| 
| style="border:1pt solid #000000;padding:0.176cm;"| This shows how a '''Negated Contact''' behaves with different types of switches.

|-
| style="border:1pt solid #000000;padding:0.176cm;"| Turn off the power
| style="border:1pt solid #000000;padding:0.176cm;"| Turn off the '''power supply'''.

|-
| style="border:1pt solid #000000;padding:0.176cm;"| 
| style="border:1pt solid #000000;padding:0.176cm;"| This brings us to the end of this tutorial.

Let us summarize

|-
| style="border:1pt solid #000000;padding:0.176cm;"| Slide 5: Summary

* Negated Coil
* Negated Contact
| style="border:1pt solid #000000;padding:0.176cm;"| In this tutorial, we learnt about working of

* '''Negated Coil'''
* '''Negated Contact'''

|-
| style="border:1pt solid #000000;padding:0.176cm;"| Slide 6: Assignment

Try cross combination and observe the results

* Normal Contact with Negated Coil
* Negated Contact with Normal Coil


| style="border:1pt solid #000000;padding:0.176cm;"| As an assignment, try cross-combination and observe the results.

*That is, '''Normal Contact''' with the '''Negated Coil'''.
*And '''Negated Contact''' with the '''Normal Coil'''.

|-
| style="border:1pt solid #000000;padding:0.176cm;"| Slide 7:

About Spoken Tutorial project
| style="border:1pt solid #000000;padding:0.176cm;"| The video at the following link summarises the Spoken Tutorial project.

Please download and watch it.

|-
| style="border:1pt solid #000000;padding:0.176cm;"| Slide 8:

Spoken Tutorial workshops
| style="border:1pt solid #000000;padding:0.176cm;"| The''' Spoken Tutorial Project''' team conducts workshops using spoken tutorials and gives certificates on passing online tests.

For more details, please write to us

|-
| style="border:1pt solid #000000;padding:0.176cm;"| Slide 9:

Forum for specific questions:
| style="border:1pt solid #000000;padding:0.176cm;"| Please post your timed queries in this forum

|-
| style="border:1pt solid #000000;padding:0.176cm;"| Slide 10:

Forum for specific questions:
| style="border:1pt solid #000000;padding:0.176cm;"| Do you have any general / technical questions on OpenPLC?

Please visit the FOSSEE forum and post your question.

|-
| style="border:1pt solid #000000;padding:0.176cm;"| Slide 11:

Acknowledgement
| style="border:1pt solid #000000;padding:0.176cm;"| Spoken Tutorial Project is funded by MHRD, Government of India.

|-
| style="border:1pt solid #000000;padding:0.176cm;"| Slide 12:

Thank you slide
| style="border:1pt solid #000000;padding:0.176cm;"| This tutorial has been contributed by FOSSEE and Spoken Tutorial Project, IIT Bombay.

And this is Harsha Priyanka from FOSSEE team, signing off.

Thanks for watching.

|}