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ClassicLadder / News: Recent posts

Monitor protocol added for remote target

Released v0.9.0 of classicladder featuring the new possibility to be able to connect to a remote target. Monitor protocol working on IP network (UDP).
One step closer for the embedded world...
Else the rungs are bigger and more elements per default (the file format has changed, .clprj extension, you can still read your old file projects!).

Posted by Marc Le Douarain 2011-04-24

Survey for an hardware project PLC for ClassicLadder


I'm thinking since a little time to lauch an hardware project of doing an hardware PLC for ClassicLadder.
Please fill the survey in english at ( or french at ), even if not interested please fill it! Many thanks.

If you have other ideas of features not present on the survey or remarks, do not hesitate to e-mail me directly.... read more

Posted by Marc Le Douarain 2009-06-23

News point at august 2008

No news on ClassicLadder since a very very long time, it is not easy to keep a regular rythm... (and the more important is to develop!)
But it's time to list the major new things, visible for you, that have been done since that time:

- First, a Windows port version is now available and generally released at the same time than the Linux one.

- The graphic rendering is now using the Cairo library.
And it is used by gtk-print (instead of the old Linux only gnome-print), which allows to have really better rendering and can works under Windows.... read more

Posted by Marc Le Douarain 2008-08-26

Switched to GTK2 and possibility to print

Perhaps it is time to annouce what you will be able to find with the latests releases I've uploaded:

* Firstly, now the application is using GTK2 (with v0.7.60)

* Secondly, and it was sometimes asked, you will now be able to print the ladder/grafcet programs you've edited (since v0.7.70/v0.7.71).
This features is using gnome-print and must be installed before.

Next improvement, will perhaps be a new function block to comes...
Wait and see.... read more

Posted by Marc Le Douarain 2006-06-20

Manual updated and users feed back wanted !

Nicaise J-Ch user and contributor for ClassicLadder has completed his cool manual (only one) with the ladder language.
You can found it here :
Nice work Dorian ! ;-)

Else, if you use ClassicLadder for any usage, and want to share your experience with others, and show that this project must go on with new features, debugs, ... send me an e-mail, or better add a little word in the forum !
I think that ClassicLadder must be used, in particular for education in schools, but if nobody tell us it, we can't know...! :-O... read more

Posted by Marc Le Douarain 2005-09-12

Modbus distributed I/O support added in v0.7.4

In this version, a new I/O type family can be used with ClassicLadder: distributed (remote) inputs/outputs using the modbus protocol.
Two modes are supported: modbus/rtu (serial) or modbus/tcp (ethernet).

Many constructors have theses types of modules in their catalog.
Official site for modbus is :

During the tests, the 2 following models have been successfully used:
-modbus/rtu (serial RS485), see:
-modbus/tcp (ethernet, ADAM-6051), see: read more

Posted by Marc Le Douarain 2005-08-16

Modbus/TCP server added in v0.7.3

The v0.7.3 release includes a Modbus/TCP server to be able to exchange datas (bits and words) between ClassicLadder and others applications...
I've only used some Modbus simulators to make successful tests, but I've not make any ones with any SCADAS softwares for now.
Very few free projects of SCADA seems to be present: I've take a look on this ones: visual (on sourceforge) and
I've failed to compile visual, and the lintouch version I've tested didn't included the Modbus/TCP plugin...... read more

Posted by Marc Le Douarain 2004-12-28

Manual available for sequential editor

Nicaise J-Ch has just been made available online a little manual for using the sequential editor of ClassicLadder.
Many thanks to him for that !

Manual here:

Posted by Marc Le Douarain 2004-12-04

v0.7.0 featuring the Sequential editor

v0.7.0 release includes the long awaited editor for the sequential language (also known as grafcet).
I've made some tests with litlle examples, and even if all isn't okay for now, it's already possible to make nice grafcets easily with the editor.
Please report any strange case you can found when doing some tests.

Have a happy new year !


Posted by Marc Le Douarain 2004-01-03

v0.6.0 released (2 November 2002)

- Added a new language : "Sequential" (sometimes also called Grafcet).
- New variables supported : Xxx and Xxx,V for the steps of the sequential.
Xxx is activity of step xx.
Xxx,V is activity time of step xx.

For people who don't know at all this technic of programming PLC, they should take a look at :

It is a major release, do not expect too much on this new language, as perhaps all isn't working as it should.
With this release, you will not be able to edit your own charts, except by hand editing of ascii files... But with some effort you can make your own to tests the functionning of this new language really interesting for sequential applications.
If you have questions or found things not working correctly, do not hesitate to mail me.... read more

Posted by Marc Le Douarain 2002-11-02

v0.5.5 released (18 August 2002)

- Added support for And, Or, Xor operators in evaluator.
- Hexadecimal constants support in evaluator
- The program can now be split in many sections.
- Some sections can be sub-routines which can be called from a rung with the new (C)all Coil
And more... see HISTORY file !

Posted by Marc Le Douarain 2002-08-18

v0.5.3 released (11 May 2002)

-Merged with the sources of MAT so that in the future we have only one version.
-Some Makefiles modifications.
-Added a vertical scollbar to be able to see many rungs at the same time.
(beware as really new and not a minor modification, this release can be rather buggy...)

Posted by Marc Le Douarain 2002-05-11

v0.5.2 released (26 january 2002)

Improvement of the editor:
-long connection (in toolbar) to create rungs faster
-grid displayed in edit mode
-'New' button to clean all
-confirmation box before deleting a rung !
-bigs elements placed in left-top when you click
And some bugfixes, see HISTORY file.

Posted by Marc Le Douarain 2002-01-26

v0.5.1 released (4 january 2002)

With the RTLinux version, the parallel ports are now scanned and connected to Ix and Qx of ClassicLadder.
Example parallel_port_test (4 inputs & 3 outputs) tested successfully here at home !

Posted by Marc Le Douarain 2002-01-04

v0.5 released (30 december 2001)

Support for RTLinux.
It allows calculations of the rungs to be done in real-time !

Posted by Marc Le Douarain 2001-12-30

v0.4 released (20 Oct 2001)

Arithmetic expressions evaluator added and used for the new "Compare" and "Operate" elements.
And as usual, not a lot tested ! ;-)

Posted by Marc Le Douarain 2001-10-20

HomePage updated for v0.3

The web page has been updated to show screenshots of the new editor, properties window,...

Posted by Marc Le Douarain 2001-08-19

v0.3 released (28 Aug 2001)

This new version includes the editor completed.
A lot of code have been added and not tested a lot since v0.2.x, so if you find any bugs then report !

Posted by Marc Le Douarain 2001-08-19