View source for OpenPLC-version1-with-LDmicro/C2/Simulation-and-Compilation/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 '''Simulation and Compilation''' in LDmicro.

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

Learning Objectives

* Simulate a ladder diagram 
* Compile a ladder diagram in LDmicro

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

* '''Simulate''' a ladder diagram and
* '''Compile''' a ladder diagram in '''LDmicro'''

|-
| style="border:1pt solid #000000;padding:0.176cm;"| Slide 3:

System Requirements

* Ubuntu Linux 18.04''' '''operating system
* LDmicro

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

* '''Ubuntu Linux''' 18.04 operating system
* '''LDmicro'''

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

* How to create a ladder diagram in LDmicro
* If not, please refer to the relevant tutorials in this series 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 create a ladder diagram in '''LDmicro'''. 
* If not, please refer to the relevant tutorials in this series on this website.

|-
| style="border:1pt solid #000000;padding:0.176cm;"| 
| style="border:1pt solid #000000;padding:0.176cm;"| First we will know about''' LDmicro simulator.'''

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

LDmicro - Simulator

* LDmicro has an in-built simulator
* It helps us to verify ladder diagram before experimenting on the actual hardware.
* It reduces the hardware damage due to improper code

| style="border:1pt solid #000000;padding:0.176cm;"| 
* '''LDmicro''' has an in-built '''simulator'''.
* It helps us to verify ladder diagram before experimenting on the actual hardware. 
* It reduces the hardware damage due to improper code.

|-
| style="border:1pt solid #000000;padding:0.176cm;"| narration
| style="border:1pt solid #000000;padding:0.176cm;"| Now, we’ll see how to simulate a ladder diagram.

We will use the ladder diagram file, '''sample.ld '''which we created earlier.

|-
| style="border:1pt solid #000000;padding:0.176cm;"| Slide 6: Code Files - sample.ld

* The file '''sample.ld '''used in this tutorial is available in the '''Code files''' link of this tutorial page 
* Please download and use them while practising

| style="border:1pt solid #000000;padding:0.176cm;"| The file '''sample.ld''' is available in the '''Code files''' link of this tutorial. 

Please download and use them while practising.

|-
| 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;"| Click ‘File -> Open’

Select the file

Click OK button
| style="border:1pt solid #000000;padding:0.176cm;"| In the menu bar, click on '''File '''and then''' Open.'''

Select the file '''sample.ld '''from the location where you have saved.

|-
| style="border:1pt solid #000000;padding:0.176cm;"| Click on “Simulate -> Simulation Mode”
| style="border:1pt solid #000000;padding:0.176cm;"| In the menu bar, click on '''Simulate '''then on '''Simulation Mode'''.

|-
| style="border:1pt solid #000000;padding:0.176cm;"| Highlight first rung
| style="border:1pt solid #000000;padding:0.176cm;"| In the '''Simulation''' '''Mode''', the whole ladder diagram changes to gray.

The cursor also disappears.

We can’t place an instruction in the '''Simulation''' mode.

|-
| style="border:1pt solid #000000;padding:0.176cm;"| Highlight second rung

Highlight first rung
| style="border:1pt solid #000000;padding:0.176cm;"| The instructions that are energized appear in bright red color.

The instructions that are not energized appear in gray color.

|-
| style="border:1pt solid #000000;padding:0.176cm;"| Highlight second rung
| style="border:1pt solid #000000;padding:0.176cm;"| Here, the '''LED2''' is energized as it is directly connected to the positive rail.

|-
| style="border:1pt solid #000000;padding:0.176cm;"| Highlight ‘switch’
| style="border:1pt solid #000000;padding:0.176cm;"| The '''LED1''' is not energized.

This is because there is a '''switch''' in between the positive rail and '''LED1'''.

For '''LED1''' to be energized, '''switch''' should be '''ON'''.

i.e, It should be given value 1.

|-
| style="border:1pt solid #000000;padding:0.176cm;"| Double click on ‘switch’ in I/O list and highlight the I/O list


Double click on ‘switch’ in the editor window and highlight the I/O list
| style="border:1pt solid #000000;padding:0.176cm;"| We can change the state of the inputs in two ways.

1. Double-click on the list that appears at the bottom of the screen.

We can see that the state changes to 1.

2. Otherwise, double-click on appropriate instruction in the ladder diagram.

|-
| style="border:1pt solid #000000;padding:0.176cm;"| Highlight state of the ‘switch’ in I/O list
| style="border:1pt solid #000000;padding:0.176cm;"| Note that '''LED1''' isn’t energized even after changing the state of the '''switch'''.

|-
| style="border:1pt solid #000000;padding:0.176cm;"| 
| style="border:1pt solid #000000;padding:0.176cm;"| This is because the change will not be reflected until the PLC cycles.

|-
| style="border:1pt solid #000000;padding:0.176cm;"| 
| style="border:1pt solid #000000;padding:0.176cm;"| For the changes to be reflected, choose either one of the below options.

# '''Simulate -> Start Real Time Simulation''' or 
# '''Single cycle''' option.

If you choose ‘'''Single Cycle'''’ option, the '''PLC''' cycles only for one time.

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


Highlight first rung
| style="border:1pt solid #000000;padding:0.176cm;"| Select ‘'''Single Cycle'''’.

Now we can observe that the first '''rung''' is energized.

That is, '''LED1''' is glowing.

|-
| style="border:1pt solid #000000;padding:0.176cm;"| Double click on the ‘switch’ in the I/O list

Highlight first rung
| style="border:1pt solid #000000;padding:0.176cm;"| Now again change the state of the ‘'''switch'''’ from 1 to 0.

We can see that the '''LED1''' is still glowing even after the '''switch''' is off.

It means that input changes are not reflected.

|-
| style="border:1pt solid #000000;padding:0.176cm;"| 
| style="border:1pt solid #000000;padding:0.176cm;"| Therefore, we need to choose ‘'''Single Cycle’''' every time we change the input state.

Use the ‘'''Single Cycle'''’ option when you want to debug the program step by step.

|-
| style="border:1pt solid #000000;padding:0.176cm;"| 
| style="border:1pt solid #000000;padding:0.176cm;"| But, this is not the case with '''Real-Time Simulation'''.

|-
| style="border:1pt solid #000000;padding:0.176cm;"| Choose ‘Simulation -> Real-Time Simulation’
| style="border:1pt solid #000000;padding:0.176cm;"| In the menu bar, select ‘'''Simulate -> Start Real-Time Simulation'''’.

|-
| style="border:1pt solid #000000;padding:0.176cm;"| Double click on the ‘switch’ in the I/O list

| style="border:1pt solid #000000;padding:0.176cm;"| Change the state of the ‘'''switch'''’ from 0 to 1.

We can observe that the state of '''LED1''' changes to 1 immediately.

Thus, the outputs gets auto-updated according to the input changes.

|-
| style="border:1pt solid #000000;padding:0.176cm;"| Click ‘Simulate -> Halt Simulation’
| style="border:1pt solid #000000;padding:0.176cm;"| We can halt simulation by clicking on ‘'''Simulate ->''' '''Halt Simulation'''’.

|-
| style="border:1pt solid #000000;padding:0.176cm;"| Click ‘SImulate -> Simulation mode’
| style="border:1pt solid #000000;padding:0.176cm;"| Then click on ‘'''Simulate'''’ and on ‘'''Simulation mode'''’ for one more time.

This will turn off the simulation mode.

|-
| style="border:1pt solid #000000;padding:0.176cm;"| narration
| style="border:1pt solid #000000;padding:0.176cm;"| Next, we’ll see the effects of cycle time on ladder diagram.

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

It includes

# reading the input states
# executing the program
# updating the outputs

| style="border:1pt solid #000000;padding:0.176cm;"| The cycle time of a PLC is the time taken from 

# reading the input states, 
# executing the program and 
# updating the outputs.

|-
| style="border:1pt solid #000000;padding:0.176cm;"| 
| style="border:1pt solid #000000;padding:0.176cm;"| Now we’ll see the effect of cycle time in '''LDmicro.'''

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

|-
| style="border:1pt solid #000000;padding:0.176cm;"| Click on Settings

Click on MCU parameters
| style="border:1pt solid #000000;padding:0.176cm;"| In the menu bar, click on '''‘Settings’'''.

Then click on '''MCU parameters.'''

|-
| style="border:1pt solid #000000;padding:0.176cm;"| Highlight cycle time

Change the cycle time to 5s

Click OK button
| style="border:1pt solid #000000;padding:0.176cm;"| By default, the cycle time is set to 10 milliseconds.

Change it to 5s i.e. 5000ms.

Then, click on the '''OK''' button in the top right of the window.

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

Click Simulate -> Start Real-time simulation

Double click on Xswitch in the I/O list
| style="border:1pt solid #000000;padding:0.176cm;"| Now start''' real time simulation''' as shown.

Change the state of the '''‘switch’''' to 1.

|-
| style="border:1pt solid #000000;padding:0.176cm;"| Point to YLED1 state.
| style="border:1pt solid #000000;padding:0.176cm;"| You can observe that the '''LED1''' doesn’t change its state immediately.

Instead it takes upto 5s to get its state updated.

|-
| style="border:1pt solid #000000;padding:0.176cm;"| Click on 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;"| Next, we will see how to compile a ladder diagram.

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

* Microcontroller selection
* MCU Parameters
* I/O assignment

| style="border:1pt solid #000000;padding:0.176cm;"| Before compiling, we need to check the following:

* Selection of proper Microcontroller

* Setting Microcontroller parameters

* Assigning ports to I/O instructions

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

|-
| style="border:1pt solid #000000;padding:0.176cm;"| Click on ‘Settings’ >> Click ‘Microcontroller’ 

| style="border:1pt solid #000000;padding:0.176cm;"| First, we’ve to select the part number of the microcontroller. 

In the menu bar, click on '''Settings -> Microcontroller''' 

|-
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.176cm;"| Highlight the list of microcontrollers

Select AVR ATmega16 40-PDIP
| style="border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.176cm;"| Here, you can observe the list of supported microcontrollers by '''LDmicro'''.

I’m using '''Atmel AVR ATmega16 40-PDIP.'''

So, I’ll select ‘'''AVR ATmega16 40-PDIP'''’.

If you are using a different microcontroller, select accordingly from the menu.

Because different microcontrollers have different hex files for the same program.

|-
| style="border:1pt solid #000000;padding:0.176cm;"| Click ‘Settings’ >> Click ‘MCU parameters’
| style="border:1pt solid #000000;padding:0.176cm;"| Now click on '''Settings -> MCU Parameters'''.

|-
| style="border:1pt solid #000000;padding:0.176cm;"| Point to ‘PLC Configuration’
| style="border:1pt solid #000000;padding:0.176cm;"| ‘'''PLC Configuration'''’ pop-up window appears.

|-
| style="border:1pt solid #000000;padding:0.176cm;"| 
| style="border:1pt solid #000000;padding:0.176cm;"| Here you can set different parameters.

|-
| style="border:1pt solid #000000;padding:0.176cm;"| Highlight ‘Cycle time’
| style="border:1pt solid #000000;padding:0.176cm;"| Change the cycle time value to 10 milliseconds.

10 milliseconds is a good value for most of the applications.

|-
| style="border:1pt solid #000000;padding:0.176cm;"| Change Crystal frequency to 16
| style="border:1pt solid #000000;padding:0.176cm;"| Next is '''Crystal Frequency:'''

* We have attached a 16 MHz external crystal in the OpenPLC hardware. 
* So set crystal frequency to 16 if you are using the same hardware. 
* Always set proper values.
* Otherwise it may cause communication and timers to behave inappropriately.

|-
| style="border:1pt solid #000000;padding:0.176cm;"| Highlight ‘Baud rate’
| style="border:1pt solid #000000;padding:0.176cm;"| Next is '''UART Baud rate''':

By default, it is in disable state.

It will be enabled only when you are using any of the serial instructions.

We will learn about this in detail when we use serial instructions.

|-
| style="border:1pt solid #000000;padding:0.176cm;"| Click the OK button
| style="border:1pt solid #000000;padding:0.176cm;"| After setting the microcontroller parameters properly, click on the '''OK''' button.

|-
| style="border:1pt solid #000000;padding:0.176cm;"| Point to the default names
| style="border:1pt solid #000000;padding:0.176cm;"| We should change the default names of the instructions before compiling the logic.

Please remember this whenever you compile the logic.

We have changed the default names for this ladder diagram in the earlier tutorial.

|-
| style="border:1pt solid #000000;padding:0.176cm;"| 
| style="border:1pt solid #000000;padding:0.176cm;"| Now, we must assign '''I/O '''pin to each '''I/O''' instruction. 

Because different I/O assignment generates different hex files.

|-
| style="border:1pt solid #000000;padding:0.176cm;"| On LDmicro interface:

Double-click on ‘switch’ in I/O list 

Select ‘PA7’

Click OK button
| style="border:1pt solid #000000;padding:0.176cm;"| To do so, double-click on ‘'''Xswitch'''’ in the '''I/O list'''.

A pop up window opens showing the unallocated pins.

Just select a pin accordingly.

I’ll select ‘'''PA7'''’, which is the 7th pin of Port A.

Then, click on the '''OK''' button.

|-
| style="border:1pt solid #000000;padding:0.176cm;"| Double-click on ‘LED1’ in I/O list 

Select ‘PC0’

Click OK

Double-click on ‘LED2’ in I/O list 

Select ‘PC1’

Click OK
| style="border:1pt solid #000000;padding:0.176cm;"| Similarly, double-click on '''YLED1''' and assign '''PC0''' as shown.

Then double-click on '''YLED2''' and assign '''PC1'''.

|-
| style="border:1pt solid #000000;padding:0.176cm;"| 
| style="border:1pt solid #000000;padding:0.176cm;"| We have assigned '''I/O pin''' to each '''I/O instruction.'''

|-
| style="border:1pt solid #000000;padding:0.176cm;"| 
| style="border:1pt solid #000000;padding:0.176cm;"| Now, let us compile.

|-
| style="border:1pt solid #000000;padding:0.176cm;"| Click ‘Compile’ >> Click ‘Compile’
| style="border:1pt solid #000000;padding:0.176cm;"| In the menu bar, click on '''Compile '''then on '''Compile.'''

|-
| style="border:1pt solid #000000;padding:0.176cm;"| Double-click on Desktop

Rename it as ‘sample’
| style="border:1pt solid #000000;padding:0.176cm;"| '''Save''' pop-up window opens.

I’ll save it in the folder '''LDmicro''' on '''Desktop''' with the same name '''‘sample.hex’.'''

|-
| style="border:1pt solid #000000;padding:0.176cm;"| Click OK button
| style="border:1pt solid #000000;padding:0.176cm;"| We will get a pop-up window which shows ‘'''Compile Successful'''’.

Click on the '''OK''' button.

|-
| style="border:1pt solid #000000;padding:0.176cm;"| Highlight ‘Compile -> Compile As’
| style="border:1pt solid #000000;padding:0.176cm;"| If you want to save it under other name choose ‘'''Compile -> Compile As'''’.

|-
| 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 9:

Summary

* Simulate a ladder diagram 
* Compile a ladder diagram in LDmicro

| style="border:1pt solid #000000;padding:0.176cm;"| In this tutorial, we learnt to

* '''Simulate''' a ladder diagram and
* '''Compile''' a ladder diagram in '''LDmicro'''

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

Assignment: 

* Change the cycle time to 3s and 10s
* Observe the changes while simulating

| style="border:1pt solid #000000;padding:0.176cm;"| As an assignment,

# Change the cycle time to 3 secs and then to 10 secs
# Observe the changes in simulation time.

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

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 12:

Spoken Tutorial workshops
| style="border:1pt solid #000000;padding:0.176cm;"| The Spoken Tutorial Project Team conducts workshops and gives certificates.

For more details, please write to us.

|-
| style="border:1pt solid #000000;padding:0.176cm;"| Slide 13:

Forum 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 14:

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 15:

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 16:

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.

|}