IDE: fix again ruberband with gtk3.
DC logical functions are now disabled when using GTK3.
Apparently using XOR was still having an effect.
Use regular black pen with no logical funciton instead.
IEC 61131-3
===========
IEC-61131 is a normative document provided by the standards organization IEC
(International Electrotechnical Commission) and describing a standard for
implementing programmable controllers.
The part 3 of this document (commonly named IEC 61131-3) specifies syntax and
semantics for programming language for programmable controllers. Beremiz
implements all the languages described in this document.
http://www.iec.eu
PLCopen TC6
===========
PLCopen is a vendor- and product-independent worldwide association defining
international standards for various topics related to control programming.
For this purpose, PLCopen has 6 technical committees.
The goal of the sixth committee (TC6) is to define a standard file format,
based on XML, for exchanging programmables controllers programmed using
IEC 61131-3 languages. Beremiz uses this file format for saving the PLC
programs of projects.
http://www.plcopen.org