In previous lessons we have discussed the Process Image Input or PII and its purpose. In this lesson we discuss the size of the PII and what will be required of you to know, as the programmer, when it comes to being able to access your I/O when the boundary of the PII is exceeded. Each PLC has a maximum area size of the PII and when exceeded, the addressing for certain I/O must be written differently. This type of addressing or I/O accessing is called Peripheral Input or Peripheral Output and must be utilized in order to access the I/O values. Let’s begin this lesson and find out how to handle Peripheral I/O.
In the previous lesson we discussed the Process Image Input or PII and its size. We wrote a simple move instruction to access an analog input only to find that just as soon as we downloaded it to the PLC, the PLC faulted and went into stop mode. In this lesson we will discuss the PII further and ...
In previous lessons we discussed the Process Image Input or PII, its purpose, size, and what happens when exceeded. We wrote a simple move instruction to demonstrate the PII boundary and faulted the PLC, diagnosed that fault, and found out how we need to handle our I/O when our PII boundary is ex...
For the last few lessons we have been discussing the Process Image Input or PII and using it within your PLC programs. We are continuing to educate on this topic by discussing the Process Image Output or PIQ. Just as we instructed previously the purpose, size, and boundary, we will inform the sam...
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