Nancyvarkey at 18:45, 10 January 2021

2021-01-10T18:45:31Z

Nirmala Venkat: Created page with " {| border="1" |- | align=center| '''Visual Cue''' | align=center| '''Narration''' |- || Slide 1: || Welcome to the spoken tutorial on '''CTD Counter''' |- || Slide 2: L..."

2020-12-23T12:38:47Z

Created page with " {| border="1" |- | align=center| '''Visual Cue''' | align=center| '''Narration''' |- || Slide 1: || Welcome to the spoken tutorial on '''CTD Counter''' |- || Slide 2: L..."

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{| border="1"
|-

| align=center| '''Visual Cue'''
| align=center| '''Narration'''
|-
|| Slide 1:
|| Welcome to the spoken tutorial on '''CTD Counter'''
|-
|| Slide 2:

Learning Objectives
* Count down (CTD) counter
||

In this tutorial we’ll learn about working of
* Count down counter
|-
|| Slide 3:

System Requirements
* Ubuntu 18.04''' '''operating system
* LDmicro
* OpenPLC version 1 Mainboard
* 24V, 2A SMPS
* USBasp programmer
* Traffic Light module
* Switchboard module
||

To record this tutorial I am using:
* '''Ubuntu Linux 18.04''' operating system
* '''LDmicro'''
* '''OpenPLC version1 Mainboard'''
* '''24V, 2A SMPS'''
* '''USBasp''' programmer
* '''Traffic Light''' module and
* '''Switchboard''' module
|-
|| Slide 4: Pre-requisites
* Working of CTU and Compare instructions
* If not, please refer to the relevant tutorials from [https://spoken-tutorial.org/ Home | spoken-tutorial.org]

|| * To follow this tutorial, you should know the working of

# '''CTU '''and
# '''Compare''' instruction.
* If not, please refer to the relevant tutorials in this series on this website.

|-
|| Slide 5: Prerequisites - Hardware setup

hardware-prerequisite.jpg
|| Connect''' SMPS''' and '''USBasp''' to the '''Mainboard''' as shown in the picture.

Keep these connections throughout this tutorial.
|-
||
|| We will create an up-down counter to understand the working of '''CTD'''.
|-
|| Open the LDmicro from the launcher bar
|| Let us open '''LDmicro'''.
|-
|| Click on Instructions -> Insert Contact >> Place the cursor to the right of Xnew >> Click on Instructions -> Insert Coil
|| Insert a '''Contact''' and a '''Coil''' as shown.
|-
|| Double-click on Xnew >> Type ‘up’ in the name box >> Click the OK button
|| Rename the Contact as '''‘up’'''.

|-
|| Place the cursor below Xup >> Click on Instructions -> Insert Contact
|| Now Insert a Contact parallel to '''Xup'''.

Rename the new Contact as '''‘down’'''.
|-
|| Place the cursor to the right of Xup >> Click Instructions -> Counters -> Insert CTU
|| To the right of '''Xup''' insert a '''CTU '''as shown here.
|-
|| Double-click the Cnew >> Type count in the name column >> Click the OK button
|| Double click on CTU.

Rename the '''CTU''' as '''‘count’. '''

The condition value is by default 0.

Don’t change it.
|-
|| Place the cursor to the right of Xdown >> Click Instructions -> Counters -> Insert CTD
|| To the right of '''Xdown''' insert a '''CTD '''as shown here.
|-
|| Double-click the Cnew >> Type count in the name column >> Click the OK button
|| Double click on CTD.

Just like CTU it has two columns, '''‘Name’''' and '''‘True if >=’'''.

Rename the '''CTD''' as '''‘count’.'''

The condition value is by default 0.

Don’t change it.
|-
|| Double-click on Ynew >> Select Internal Relay >> Type relay in the name box >> Click the OK button
|| Now configure the Coil as Internal Relay and rename it as '''‘relay’'''.
|-
||
|| This is because here we don't need any physical output from CTU & '''CTD'''.
|-
|| Click Edit -> Insert Rung below
|| Now place a rung below as shown here.
|-
|| Place the cursor in the new rung >> Click on Instructions -> Comparison operators -> Insert GEQ
|| In the new rung insert a greater than or equal to Compare instruction.
|-
|| Double-click on greater than or equal to Compare instruction >> Type Ccount in the ‘Closed’ if: column >> Type 3 in the >= column
|| Double-click on the compare instruction.

Compare '''Ccount''' variable with 3.

That is in the Closed if column enter '''Ccount'''.

In the >= column enter 3.

Click on the OK button
|-
|| Place the cursor to the right of Compare instruction >> Click on Instructions -> Insert Coil
|| Now to the right of it insert a Coil.
|-
|| Double click on Ynew >> Type LED in the name column
|| Rename it as '''‘LED’'''.
|-
||
|| We will now check the working of this logic.
|-
|| Click Simulate -> Simulation mode >>

Click Simulate -> Real-time simulation
|| Let us turn on the simulation mode.

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

Next, start real-time simulation as shown.
|-
|| Highlight the states of all the instructions in the IO list
|| We can observe initially that the state of every instruction is 0 except for '''Rrelay'''.
|-
|| Double click on Xup
|| Double click on '''Xup''' to change its state to 1.
|-
|| Highlight the state of Ccount
|| We can observe the state of the '''Ccount''' changes to 1.
|-
|| Highlight the state of Ccount
|| Keep changing the state of '''Xup '''by double clicking on it until '''Ccount''' value reaches 3.
|-
|| Highlight the state of YLED
|| We can observe the state of '''YLED''' changes to 1.
|-
||
|| Just like in the '''CTU''' example.
|-
|| Double click on Xdown
|| Now change the state of '''Xdown''' to 1.
|-
|| Highlight the state of Ccount
|| We can observe the '''Ccount''' value changes to 2.

That is decreased by 1.
|-
|| Highlight the state of YLED
|| Also, the state of '''YLED''' goes back to 0.

The state of '''YLED''' will be 1 only when '''Ccount''' value is >= 3.
|-
|| Double click on Xdown
|| Change the state of '''Xdown''' back to 0.
|-
|| Highlight the state of Ccount
|| The value of '''Ccount''' is still 2.
|-
|| Highlight the state of Ccount
|| The '''CTD''' decreases the count value by 1 only with the rising edge of its input.
|-
||
|| Thus the working of '''CTU''' and '''CTD''' is similar.

The only difference is '''CTD''' decrements the counter value.
|-
||
|| We can also reset the '''CTD''' using '''RESET''' instruction.
|-
|| Click Simulate -> Halt Simulation >> Click Simulate -> Simulation Mode
|| Now, turn off the simulation mode.

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

Then click '''Simulate''' and '''Simulation Mode.'''
|-
||
|| Now let us compile the logic.

The detailed steps on how to compile and save the logic are explained in the earlier tutorials.
|-
|| Click on Settings >> Click on Microcontroller >> Select AVR ATmega16 40-PDIP

Click on Settings >> Click on MCU parameters >> Change Crystal frequency to 16
|| Click on '''Settings''' and select the microcontroller '''AVR ATmega16 40-PDIP.'''

Adjust its parameters as shown here.
|-
|| Double-click on Xswitch in I/O list >> Select PC0 >> Click OK button

Double-click on YLED in I/O list >> Select PA0 >> Click OK button
|| Assign pin '''PC0''' to '''Xup '''and '''PC1''' to '''Xdown'''.

Assign pin '''PA0''' to '''YLED'''.
|-
|| Click on Compile >> Click on Compile >> Go to Desktop/LDmicro folder >> Rename it as ‘ctd.hex’ >> Click on Save.

Click OK button
|| Compile the logic as '''ctd.hex.'''
|-
|| Click on File >> Click on Save >> Go to Desktop/LDmicro folder >> Rename it as ‘ctd.ld’ >> Click on Save
|| Then save the ladder diagram as '''ctd.ld.'''
|-
||
|| We will now see the working of this logic on hardware.
|-
|| Connect Mainboard to PC using USBasp

laptop-usbasp.jpg

|| Connect the '''Mainboard''' to your laptop using '''USBasp'''.

Turn on the power supply.
|-
|| Open terminal >> Type cd Desktop/LDmicro >> Press ENTER >> type ‘'''avrdude -c usbasp -p m16 -U flash:w:ctd.hex’ '''>> Press ENTER
|| 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'''.
|-
|| Remove the '''USBasp''' connection from the laptop.
|| Turn off the power supply.

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

This will prevent any hardware damage.
|-
|| ctd.png
|| Let us see the connection details now.
|-
|| ctd.png
|| Connect '''GND''' pin of the red LED of '''Traffic Light''' module to '''GND''' of the '''Mainboard'''.

Then connect the '''+5V pin''' of the red LED to '''PA0''' pin of the '''Mainboard'''.
|-
|| ctd.png
|| Connect '''GND''' and 5V of '''switchboard''' to GND and 5V of the '''Mainboard''' respectively.

Connect '''NO1''' to '''PC0''' of the '''Mainboard'''.

Then connect '''NO2''' to '''PC1''' of the '''Mainboard'''.

Make the connections as shown in the picture.
|-
||
|| After making all the connections properly, turn on the power supply.
|-
||
|| Initially the red LED will not glow.
|-
||
|| It will glow only when '''NO1''' is pressed for at least three times.

So, press the switch''' NO1''' for 3 times.
|-
||
|| Now the count value is 3.
|-
||
|| Press the switch NO2.

The count value becomes 2 and the LED will turn off.

Thus CTD decreases the count value by 1 after every switch press.

Turn off the power supply.
|-
|| Slide : Where can an up-down counter be used?* The up-down counter can be used when we need to <span style="background-color:#ffffff;">count finished products</span>.
* CTU will increment the count value when a product is finished.
* CTD will decrement the count of products that fail the quality test.

|| Where can an up-down counter be used?

The up-down counter can be used when we need to <span style="background-color:#ffffff;">count the finished products</span>.

CTU will increment the count value when a product is finished.

CTD will decrement the count of products that fail the quality test.

|-
||
|| This brings us to the end of this tutorial.

Let us summarize.
|-
|| Slide 5: Summary* Count down (CTD) counter

|| In this tutorial we learnt about working of * Count down counter
|-
|| Slide 6:

About Spoken Tutorial project
|| The video at the following link summarises the Spoken Tutorial project.

Please download and watch it
|-
|| Slide 7:

Spoken Tutorial workshops
|| The''' Spoken Tutorial Project''' team:* conducts workshops using spoken tutorials and
* gives certificates on passing online tests.

For more details, please write to us
|-
|| Slide 8:

Forum for specific questions:
|| * Please post your timed queries in this Forum

|-
|| Slide 19:

Forum for specific questions:
|| Do you have any general / technical questions on OpenPLC?

Please visit the FOSSEE forum and post your question.
|-
|| Slide 10:

Acknowledgement
|| Spoken Tutorial Project is funded by MHRD, Government of India.
|-
|| Slide 11:

Thank you slide
|| 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.
|-
|}

OpenPLC-version1-with-LDmicro/C3/CTD-Counter/English - Revision history

Nancyvarkey at 18:45, 10 January 2021

Nirmala Venkat: Created page with " {| border="1" |- | align=center| '''Visual Cue''' | align=center| '''Narration''' |- || Slide 1: || Welcome to the spoken tutorial on '''CTD Counter''' |- || Slide 2: L..."