Mitsubishi Electric AJ71C24-S6 User Manual page 126

8. COMMUNICATIONS USING DEDICATED PROTOCOLS
MELSEC-A
8.4.2 Control format 2
T o read data
rom the PC
5PU to the
:omouter
St. No. :Station nu!
To
write data
rom the
:omputer to
he PC CPU
Description
Control Protocol
H L H L H L H L
I
Transmission sequence
-
or
E
Camputer
0
H , L
or
.
A
slack
St.
NO. NO.
H L H , L I
~ a ~ ~ ~ t ~ ~
3emarks
PJ71C24
2.
H , L
Block
NO.
H , L
(1)The sum check is enabled by DIP switch 21.
The
sum
check code only exists when the sum check
is
enabled by turning DIP switch 21 0 ,
(2)The sum check is made for characters marked
"*"
in these diagrams.
(3) In these diagrams, the contents of "character area A", "character area B", and "character are
depend on the individual system. For details, see the relevant sections. The contents <
character areas are the same for all 4 formats.
Block
NO.
H , L
PC
No.
H , L
AJ71C24
-
Sf
NO.
H , L
h.
NO.
H , L
Corn-
rnand
H , L
Character
area B
PC
NO.
H , L
Block
NO.
Sum
: " , " :
H, L
PC
NO.
H, L
Transmission sequence
Meaage
walftirne
H , L
St.
NO.
PC
NO
Character
areaA
Cam-
mand
H , L
or
H , L
zck
code
H , L
m l t i m e
Mea~geChacacter
areaC
H , L
Zzk
code
H , L