Omron CJ1W-SCU22, Руководство по эксплуатации, Страница: 357 / 478

R-23
A Standard System Protocol
CJ-series Serial Communications Units Operation Manual for NJ-series CPU Unit(W494)
R
-2
Com
p
o
W
a
y
/F Mast
er Pr
otoc
o
l
Re
f
R
-2-8
Str
ucture of
the Protocol
• Send word order: Leftmost to rightmost
• Receive word order: Leftmost to rightmost
This sequence converts the specified data beginning with the command code (MRC, SRC) to ASCII
and sends it to the specified Unit. The response is converted to hexadecimal and stored starting at the
specified word.
Send Data Word Allocation (3rd Operand of PMCR(260))
Set the number of send bytes to twice the number of bytes in memory. This is necessary because
the data is converted to ASCII data before being sent. The frames are created and sent in order
from the leftmost word to rightmost word of the I/O memory address.
Send/Receive with ASCII Conversion, with Response:
(Sequence No. 606 (Hex 025E))
Offset Contents (data format) Data
+0 Number of send data words (4 digits Hex) 0005 to 00FA hex (5 to 250 decimal)
+1 (Undefined) Node No.
(2 digits BCD) 00 to 99
+2 MRC (2 digits hex) SRC (2 digits hex) Set the command code for the required service
+3 Number of send bytes (4 digits hex) Number of data bytes from the next byte after the
command code (MRC, SRC) until the byte just
before the ETX.
0000 to 03D8 hex (0 to 984 decimal)
Note: The data is converted to ASCII in the com-
munications line, so the number of data bytes is
doubled from S+4 and onwards.
+4
on Send data (4 digits hex) The data specified in hexadecimal here will be
converted to ASCII and the number of send bytes
specified in S+3 will be sent in word order from the
leftmost to the rightmost word.
Send data
First word of
send data
Number of send data words
+0
+1
+2
+3
+4
on
(Undefined)
Number of send bytes
MRC
SRC
Node No.
1 2 3 4
5 6 7 8
Rightmost word
Leftmost word
Send data words Send frame
"56" "78" "12" "34"