User manual

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When several CPU modules are connected to one communication
network, they must use individual ID numbers. The PLC’s network ID
number is configured using the WinGPC.
Communication steps
The NX CPU can support 2-step or 4-step communication methods.
The communication methods are easily distinguished each other by
selecting and sending the function code of the Q frame. Even for the 4-
step method, the 2-step method can be used for the repeated function.
This function sends and receives the only RR repeatedly when you
want to redo the frame you sent with query, allowing users to quickly
monitor data.
• 2-step communication method
This method allows users to easily and directly program
communication since it only uses the simple
Q
→ R steps.
2-step configuration:
Q(step 1)
→ R(step 2)
Repeated function code:
Q(step 1)
→ R(step 2) → RR(step 1) → R(step 2) →
RR(step 1)
→ R(step 2)....
• 4-step communication method
Q
→ QA → RR → R.
2-step method can be used for the response to the repeated
function code.
4-step configuration:
Q(step 1)
→ QA(step 2) → RR(step 3) → R(step 4)
Repeated function code:
Q(step 1)
→ QA(step 2) → RR(step 3) → R(step 4) →
RR(step 1)
→ R(step 2)…