3.5. System Area of CC-Link

3.5. System Area of CC-Link

 

When using RX/RY + RWr/RWw mode, you cannot use the last 2 bytes of the usable RX/RY area because they are the system areas.

Table3-13 shows the system area. Of the areas, “Reserved area” currently can be used but will be changed for different usage in the future version of the CC-Link protocol.

Please restrain from using the “Reserved area” as much as possible as it can cause malfunction due to lack of compatibility.

 

Table 3‑13 System Area of CC-Link

Link input	Signal name	Link output	Signal name
RXn0	Reserved area	RYn0	Reserved area
RXn1		RYn1
RXn2		RYn2
RXn3		RYn3
RXn4		RYn4
RXn5		RYn5
RXn6		RYn6
RXn7		RYn7
RXn8	Initial data processing request flag	RYn8	Initial processing complete flag
RXn9	Initial data setting complete flag	RYn9	Initial setting request flag
RXnA	Error status flag	RYnA	Error setting request flag
RXnB	Remote station ready	RYnB	Reserved area
RXnC	Reserved area	RYnC
RXnD		RYnD
RXnE	OS definition	RYnE	OS definition
RXnF		RYnF
		Number of stations	1	n=1
			2	n=3
			3	n=5
			4	n=7

 

Because “RXn8~RXnB” and “RYn8~RYnA” use the self-handshake of CC-Link communication, common I/O cannot be used. If you have to use this area inevitably, you must stop the handshake operation of this area of the Hi5 Controller. For this set the system signal option as shown in [Figure 3.8].

 

But, please avoid this method as it does not satisfy the CC-Link standard.

 

If you are utilizing the handshake of RXn8~RXnB and RYn8~RYnA on the PLC side, you must set the system signal to “System”.

 

 

 

Figure 3.8 System Signal Setting