7 - 5
MELSEC-
7 USING FRAMES WHEN EXCHANGING DATA
(1) Transmitting with a frame added
Using the transmission table (
R2
122H to 185H) of the No. designated in the
transmission table head No. designation (
R2
120H), the frames having the No.
of points designated in the No. of transmission table (
R2
121H)
are transmitted.
The data transmission method is the same as when a frame is not added (non-
procedural communication), so refer to Chapter 6.
(2) Designating the transmission data in the transmission area
When using the transmission data in the transmission area, designate the frame
No. (8000
H).
The data equivalent to the word/byte size designated in the transmission data
size designation area will be transmitted from the transmission area.
(3) Setting the buffer memory
The items to be set for the buffer memory used when transmitting data using the
transmission frame 2 area are shown below.
R2 buffer memory
address
Name Details
R2
120H
Transmission table
head No. designation
When transmitting frames using the transmission frame 2 area, designate
the head No. of the transmission table in which the data to be transmitted
is designated.
0 : Do not transmit with frame 2 area (default value)
1 to 100 : Head No. of transmission data designation destination in
transmission table
R2
121H
No. of transmission
table
When transmitting frames using the transmission frame 2 area, designate
the No. of transmission tables as 1 to 100 from the table position
designated in the transmission table head No. designation (
R2
120H).
0 : Do not transmit with frame 2 area (default value)
1 to 100 : No. of transmission table
R2
122H to 185H
Transmission table
designation
(No. 1 to No. 100)
For frame transmission or monitor transmission using the transmission
frame 2 area, designate the No. of the data frame to be transmitted from
the frames registered in R2.
0
H (0) : No designation (default value)
1
H to 161H (1 to 353) : Designate default registration frame
3E8
H to 4AFH (1000 to 1199) : Designate user registration frame
8000H (–32768) : Designate transmission area data
(Example) Transmission table head No. designation: 5, transmission table size: 3,
Transmission table designation (No. 5, 6,7): 02
H (STX), 138H (RD), 107H (ETX, FFF1H)
R2
External device,
such as ID controller
ETX, FFF1
H
(No.7)
'RD'
(No.6)
STX
(No.5)
Transmission
table head No.!
Transmission table size
