Mitsubishi Electric AJ71C24-S6 User Manual page 123

8.
COMMUNICATIONS USING DEDICATED PROTOCOLS
MELSEC-A
8.3
Basics of Dedicated Protocol Control Procedures
(I) Reading data by the computer from the AJ71C24
Computer
Area A
(a) Areas A and C indicate transmission from the external device to the
AJ71 C24.
(b) Area B indicates transmission from the AJ71C24 to the external
device.
(c) Computer programs are created so that all data is transmitted from
left to right.
(Example: In area A, data is transmitted to the right after the ENQ
signal.)
(d) Area C of the program completes data communications (whether
communications are being carried out or not) and permits the next
data communications to be carried out.
(2) Writing data by the computer to the AJ71C24
N AreaA
computer
~
~
!
~
Area B
1
I K ,
(a) Area A indicates transmission from the external device to the
AJ71C24.
(b) Area B indicates transmission from the AJ71C24 to the external
device.
(c) Computer programs are created so that all data is transmitted from
left to right.
(Example: In Area A, data is transmitted to the right after the ENQ
signal.)