Mitsubishi Electric GT16, User Manual

Page: 1154 / 1306

61 - 22
61. MICROCOMPUTER CONNECTION (SERIAL)
61.5 Message Formats
(8) Sum check code
The sum check code is obtained by converting the lower 1 byte (8 bits) of the result (sum), after having added
the sum check target data as binary data, to 2-digit ASCII code (Hex).

Message format
(1) Batch read in word units (RD) command
(a) When reading a word device
The following shows an example of reading the two points of the virtual devices D100 and D101.
(Assuming D100=0102
H
, D101=0304
H
are stored.)
Sum check is performed in this range.
02
H
STX
03
H
ETX
(H) (L)
B C
42
H
43
H
Sum
Check
(H) (L)
Command
R D
52
H
44
H
(H) (L)
Address
0 1
30
H
31
H
0
30
H
0
30
H
(H) (L)
Number of
points
0 2
30
H
32
H
52
H
+ 44
H
+ 30
H
+ 31
H
+ 30
H
+ 30
H
+ 30
H
+ 32
H
+ 03
H
= 1BC
H
D100
D101
0102
H
0304
H
Item Message format
Request message
(host
GOT)
Response message
during normal
communication
(GOT
host)
Response message
during faulty
communication
(GOT
host)
(format 1: GOT-A900 Series microcomputer connection (format 1))
(format 2: GOT-A900 Series microcomputer connection (format 2))
Sum check is performed in this range.
02
H
STX
03
H
ETX
(H) (L)
B C
42
H
43
H
Sum
Check
(H) (L)
Command
R D
52
H
44
H
(H) (L)
Address
0 1
30
H
31
H
0
30
H
0
30
H
(H) (L)
Number of
points
0 2
30
H
32
H
Sum check is performed in this range.
02
H
STX
03
H
ETX
(H) (L)
8 D
38
H
44
H
Sum
Check
(H) (L)
0 1
30
H
31
H
0
30
H
2
32
H
(H) (L)
0 3
30
H
33
H
0
30
H
4
34
H
Data 1 (D100) Data 2 (D101)
15
H
NAK
The above is a case
where the sum check error
(06
H
) has occurred.
15
H
NAK
06
H
Error
code