36
The following diagram must be broken down into two blocks and each of
these then broken into two blocks before it can be coded. As shown below,
blocks a and b require an AND LD. Before AND LD can be used, however,
OR LD must be used to combine the top and bottom blocks on both sides,
i.e., to combine a1 and a2; b1 and b2.
0000
0001
0004
0005
0103
Block
a
Block
b
0006
0007
Block
b2
Block
b1
0002
0003
Block
a2
Block
a1
Blocks a1 and a2
Blocks b1 and b2
Blocks a and b
Address
Instruction
Operands
0000
LD
0000
0001
AND NOT
0001
0002
LD NOT
0002
0003
AND
0003
0004
OR LD
---
0005
LD
0004
0006
AND
0005
0007
LD
0006
0008
AND
0007
0009
OR LD
---
0010
AND LD
---
0011
OUT
0103
This type of diagram can be coded easily if each block is worked with in or-
der first top to bottom and then left to right. In the following diagram, blocks a
and b would be combined with AND LD as shown above, and then block c
would be coded and a second AND LD would be used to combine it with the
execution condition from the first AND LD, and so on through to block n.
Block
a
Block
b
00
Block
n
Block
c
The Ladder Diagram
Section 4-3
Summary of Contents for SYSMAC C20K
Page 1: ...Cat No W146 E1 5 Programmable Controllers SYSMAC C20K C28K C40K C60K ...
Page 2: ...K type Programmable Controllers OPERATION MANUAL Revised July 1999 ...
Page 3: ...iv ...
Page 5: ...vi ...
Page 19: ...7 SECTION 2 Hardware Considerations 2 1 Introduction 2 2 Indicators 2 3 PC Configuration ...