Omron DR 170 14 Server User Manual


 
Klinkmann Automation Omron Ethernet DAServer 37
Omron Ethernet DAServer Ver 1.x User Manual Rev 1.4 17014m14
High-order Byte Only the high-order byte (MSB - most significant 8-bits) of each
word is used for read. To use this format, append the suffix 'D'
to the item name.
Both Bytes Both bytes of each word are used for read/write. To use this
format, append the suffix 'C' to the item name.
Note: All bytes in the specified memory range will be used. If the string is shorter
than the range of memory specified, it will be padded with '\0'. If the string is longer
than the range of memory specified, the string will be truncated.
For example, assume the following memory contents (numeric values shown in
hex):
MSB
LSB
DM10
41 42 "AB"
DM11
43 44 "CD"
DM12
45 46 "EF"
Read:
DM10 – DM12C
returns ABCDEF
DM10 – DM11D
returns AC
DM10 – DM12E
returns BDF
Write:
DM10 - DM12C after written with "ABCD"
MSB
LSB
DM10
54 65 "AB"
DM11
73 74 "CD"
DM12
0 0 " "
DM10 - DM12E after written with "ABCDE"
MSB
LSB
DM10
0 41 "A"
DM11
0 42 "B"
DM12
0 43 "C"
Imortant Note!
Do not operate with item names, which have addresses outside really existing PLC
data and memory area! It will lead to communication failures, because the DAServer
recognizes item name error only if item name goes out of range represented in the item
names table. Usually the information like following will be logged to logger if some item
with address in inaccessible memory area is used (MRC:11 and SRC:03 informs about
"Parameter error: the first address is in an inaccessible area")
<Socket.Controller>: FINS command 0101 failed (resp. error code 1103). Parameter
error: the first address is in inaccessible area.