1. PLC Concepts

1-11

1.6 Conversion between Ladder Diagram and Instruction List Mode

Ladder Diagram

X0 X2 X1
X1
M1
C0 Y0
SET S0
M2 Y0
M0
X10
Y
10
SET S10
S0
S
X11
Y
11
SET S11
S10
S
SET S12
SET S13
X12
Y
12
SET S20
S11
S
X13 S0
RET
S20
SS12
SS13
S
X0 CNT C0 K10
X1 M0
C0
X1
M2
RST C0
M1
M2
END

Instruction

LD X0
OR X1
LD X2
OR M0
ORI M1
ANB
LD M2
AND Y0
ORB
AN I X1
OUT Y0
AND C0
SET S0
STL S0
LD X10
OUT Y10
SET S10
STL S10
LD X11
OUT Y11
SET S11
SET S12
SET S13
STL S11
LD X12
OUT Y12
SET S20
STL S20
STL S12
STL S13
LD X13
OUT S0
RET
LD X0
CNT C0 K10
LD C0
MPS
AND X1
OUT M0
MRD
AN I X1
OUT M1
MPP
AN I M2
OUT M2
END
OR
block
ANI
Multiple
outputs
RST C0
OR
block
Block in series
AND
block
Block in parallel The output
continues
based on
status of
Start of step ladder
Output Y10 and
transfer of step point
Read S10 status
Output Y11 and
transfer of step points
Read S11 status
S11 operates with X12
Output Y 12 and
transfer of step points
Convergence of
multiple status
End of step
ladder
Read X13 status and
transfer of step point
Return
Read C0
Multiple
outputs
End of program
S0 status operates with X10