plc advanced functions - 16.26
16.6DESIGN CASES
16.6.1If-Then
Problem: Convert the following C/Java program to ladder logic.
void main(){ int A;
for(A = 1; A < 10 ; A++){ if (A >= 5) then A = add(A);
}
}
int add(int x){
x = x + 1; return x;
}
Solution:
plc advanced functions - 16.27
Program 2 |
S2:1/15 |
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A
Program 3
Figure 16.28 C Program Implementation
FOR
label number 0 index N7:0 initial value 1 terminal value 10 step size 2
JSR
Program File 3 Input par N7:0 Return par N7:0
NXT
label number 0
SBR
Input par N9:0
ADD
SourceA N9:0
SourceB 1
Dest N9:0
RET
Return par N9:0
16.6.2 Traffic Light
Problem: Design and write ladder logic for a simple traffic light controller that has a single fixed sequence of 16 seconds for both green lights and 4 second for both yellow lights. Use either stacks or sequencers.
Solution: The sequencer is the best solution to this problem.