Filter
Top Products
6 - 25
MELSEC-
A
6 EXCHANGING DATA WITH AN EXTERNAL DEVICE
(2) Timing chart
1)
2)
3)
4)
5) 7)
6)
8)
9)
10) 11)
12) 13)
Carried out with sequence program
Carried out by R2
External device
Intelligent device station
access request (RY(n+1)E)
Intelligent device station
access complete (RX(n+1)E)
Master station Transmission buffer
Master station Reception buffer
R2 Reception area
OS reception area
Reception read complete
signal (RYn2)
Reception normal/error read
request signal (RXn2/RXn3)
Word device
Programmable
controller CPU
No. Details Control side
1) The reception data is stored in the reception area via the OS reception area. R2
2)
When the reception from the external device is completed
(
*
1
)
, the reception normal read request
signal (RXn2) or reception error read request signal (RXn3) turns ON.
R2
3) The read control data is stored in the master station transmission buffer. Program
4) The intelligent device station access request signal (RY(n+1)E) turns ON. Program
5) The contents set in the control data are conveyed to R2. R2
6) The control data and reception data are stored in the master station reception buffer. R2
7) The intelligent device station access complete signal (RX(n+1)E) turns ON. R2
8) The intelligent device station access request signal (RY(n+1)E) turns OFF. Program
9) The intelligent device station access complete signal (RX(n+1)E) turns OFF R2
10) The reception data is read from the master station reception buffer. Program
11) The reception read complete signal (RYn2) turns ON. Program
12) The signal turned ON in step 2) turns OFF. R2
13) The reception read complete signal (RYn2) turns OFF. Program
*1 Indicates the storage of the reception end data size data or the data to the reception end frame into the
reception area.