12.05.2014 Views

Automating Manufacturing Systems - Process Control and ...

Automating Manufacturing Systems - Process Control and ...

Automating Manufacturing Systems - Process Control and ...

SHOW MORE
SHOW LESS

You also want an ePaper? Increase the reach of your titles

YUMPU automatically turns print PDFs into web optimized ePapers that Google loves.

plc il - 18.3<br />

LD I:000/0<br />

AND( I:000/1<br />

OR( I:000/2<br />

ANDN I:000/3<br />

)<br />

)<br />

I:000/0<br />

I:000/1<br />

(<br />

AND I:000/0<br />

I:000/2<br />

(<br />

OR I:000/1<br />

(<br />

AND I:000/0<br />

result_1<br />

(<br />

OR I:000/1<br />

(<br />

AND I:000/0<br />

result_2<br />

(<br />

AND I:000/0<br />

result_3<br />

Given:<br />

I:000/0 = 1<br />

I:000/1 = 0<br />

I:000/2 = 1<br />

I:000/3 = 0<br />

1<br />

0<br />

(<br />

AND 1<br />

1<br />

(<br />

OR 0<br />

(<br />

AND 1<br />

1<br />

(<br />

OR 0<br />

(<br />

AND 1<br />

1<br />

(<br />

AND 1<br />

1<br />

AND 1<br />

1<br />

Given:<br />

I:000/0 = 0<br />

I:000/1 = 1<br />

I:000/2 = 0<br />

I:000/3 = 1<br />

0<br />

1<br />

(<br />

AND 0<br />

0<br />

(<br />

OR 1<br />

(<br />

AND 0<br />

0<br />

(<br />

OR 1<br />

(<br />

AND 0<br />

0<br />

(<br />

AND 1<br />

0<br />

AND 1<br />

0<br />

Figure 18.2<br />

Using a Stack for Instruction Lists<br />

A list of operations is given in Figure 18.3. The modifiers are;<br />

N - negates an input or output<br />

( - nests an operation <strong>and</strong> puts it on a stack to be pulled off by ’)’<br />

C - forces a check for the currently evaluated results at the top of the stack<br />

These operators can use multiple data types, as indicated in the data types column.<br />

This list should be supported by all vendors, but additional functions can be called using<br />

the CAL function.

Hooray! Your file is uploaded and ready to be published.

Saved successfully!

Ooh no, something went wrong!