PLC Programming

5 - Editors in CoDeSys
The contact is preset with the text "". You can click on this text and change it to the desired
variable or the desired constant. For this you can also use the Input Assistant.
It is possible to display the variable name with linebreaks. Also a separate comment can be inserted
for the contact. For a description see 'Insert' 'Contact' .
'Insert' 'Function Block' in LD
Shortcut: +
Use this command in order to insert an operator, a function block, a function or a program as a POU.
For this, the connection between the contacts and the coils, or a coil, must be marked. The new POU
at first has the designation AND. If you wish, you can change this designation to another one. For this
you can also use the Input Assistant. Both standard and self-defined POUs are available.
The first input to the POU is placed on the input connection, the first output on the output connection;
thus these variables must definitely be of type BOOL. All other in- and outputs of the POU are filled
with the text „". These prior entries can be changed into other constants, variables or addresses.
For this you can also use the Input Assistant.
'Insert' 'Coil' in LD
Symbol:
Shortcut: +
You can use this command in the LD editor to insert a coil in parallel to the previous coils.
If the marked position is a connection between the contacts and the coils, then the new coil will be
inserted as the last. If the marked position is a coil, then the new coil will be inserted directly above it.
The coil is given the text "" as a default setting. You can click on this text and change it to the
desired variable. For this you can also use the Input Assistant.
It is possible to display the variable name with linebreaks. Also a separate comment can be inserted
for the coil. For a description see 'Insert' 'Contact'
POUs with EN Inputs
If you want to use your LD network as a PLC for calling up other POUs , then you must merge a POU
with an EN input. Such a POU is connected in parallel to the coils. Beyond such a POU you can
develop the network further, as in the Function Block Diagram. You can find the commands for
insertion at an EN POU under the menu item 'Insert' 'Insert at Blocks'.
An operator, a function block, a program or a function with EN input performs the same way as the
corresponding POU in the Function Block Diagram, except that its execution is controlled on the EN
input. This input is annexed at the connecting line between coils and contacts. If this connection
carries the information "On", then the POU will be evaluated.
If a POU has been created once already with EN input, then this POU can be used to create a
network. This means that data from usual operators, functions, and function blocks can flow in an EN
POU and an EN POU can carry data to such usual POUs.
If, therefore, you want to program a network in the LD editor, as in FBD, you only need first to insert
an EN operator in a new network. Subsequently, from this POU, you can continue to construct from
your network, as in the FBD editor. A network thus formed will perform like the corresponding network
in FBD.
'Insert' 'Box with EN in LD'
Use this command to insert a function block, an operator, a function or a program with EN input into a
LD network.
The marked position must be the connection between the contacts and the coils (Cursor Position 4) or
a coil (Cursor Position 3). The new POU is inserted in parallel to the coils and underneath them; it
contains initially the designation "AND". If you wish, you can change this designation to another one.
For this you can also use the Input Assistant.
CoDeSys V2.3 5-27