LSIS XBE-DC08A, Руководство пользователя, Страница: 1052 / 1284

Chapter 2 Built-in Cnet communication
2-54
B
u
ilt
-in
C
omm
2.5.2 Detail of instruction
1) Individual reading of device (R(r)SS)
This is a function that reads PLC device specified in accord with memory data type. Separate device memory can be
read up to 16 at a time.

PC request format
Format
name
Header
Station
No.
Comman
d
Command type
Number
of blocks
Device
length
Device name
....
Tail
Frame
check
Ex. of
frame
ENQ H20 R(r) SS H01 H06 %MW100 EOT BCC
ASCII
value
H05
H323
0
H52(72) H5353 H3031 H3036 H254D57313030 H04
Item Description
BCC
When command is lowercase(r), only one lower byte of the value resulted by adding 1 Byte
each to ASCII values from ENQ to EOT is converted into ASCII and added to BCC. For
example, the BCC of the above frame is gotten as below:
H05+H32+H30+H72+H53+H53+H30+H31+H30+H36+H25+H4D+H57+H31+H30+H30+H04
= H03A4 Therefore BCC value is A4 (ASCII value : H4134).
Number of
Blocks
This specifies how much of the blocks composed of "[device length][device name]" are in this
request format. This can be set up to 16. Therefore, the value of [Number of blocks] must be
set between H01(ASCII value:3031)-H10(ASCII value:3030).
Device length
(Length of
device name)
This indicates the number of name's characters that means device, which is allowable up to 16
characters. This value is one of ASCII converted from hex type, and the range is from
H01(ASCII value:3031) to H10(ASCII value:3130). For example, if the device name is %MW0,
it has 4 characters to be H04 as its length. If %MW000 characters to be H06.
Device name
Address to be actually read is entered. This must be ASCII value within 16 characters, and in
this name, digits, upper/lower case, '%' is only allowable to be entered.
•
BCC value is low 1byte in the sum of each byte from ENQ to EOT.
•
In case of making actual frame, 'H' is not attached. Because the number data of frame indicates
hexadecimal.
1
block
(
setting can be repeated up to max. 16 blocks
)
Note