Mitsubishi MELSEC Q Series Reference Manual page 139

(3) Contents of the character areas during multiple block batch read
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3 WHEN COMMUNICATING USING THE QnA COMPATIBLE 3E/3C/4C FRAMES OR 4E FRAME
and batch write
This section explains what is contained in the character area when a multiple
block batch read or batch write function is performed.
The contents are the same as when using the other commands, except for the
data shown below.
(a) Number of word device blocks and number of bit device blocks
This value designates the number of word device blocks or bit device
blocks to be sent directly after this data field in the batch read or batch write
to the word device or bit device, respectively.
1) Data communication in ASCII code
Each number of blocks are converted to 2-digit ASCII code
(hexadecimal) and transmitted.
(Example)
For 5 blocks
In case of 20 blocks : Converted to "14", and transmitted
2) Data communication in binary code
1-byte numeric value indicating each number of blocks is transmitted.
(Example)
In case of 5 blocks
In case of 20 blocks : 14
3) Designate each number of blocks so the following condition is satisfied:
120  number of word device blocks + number of bit device blocks
4) When setting either number of blocks to 0, the corresponding device
number, device code, number of device points, and data designations
are not necessary.
(b) Word device number and bit device number
This value designates the head word device or bit device for each block to
which batch read or batch write is performed, where contiguous word/bit
devices are considered one block.
1) Data communication in ASCII code
The head device number of each block is converted to 6-digit ASCII
code and transmitted.
(Example)
Internal relay M1234 and link register W1234:
The internal relay M1234 is converted to "001234" or "
and the link register W1234 is converted to "001234" or "
In both cases, the transmission starts from "0" or " ".
2) Data communication in binary code
The head device number of each block is indicated in a 3-byte numeric
value and transmitted.
(Example)
Internal relay M1234 and link register W1234:
The internal relay M1234 is converted to 0004D2
in the order of D2
The link register W1234 is converted to 001234
the order of 34
: Converted to "05", and transmitted
sequentially from "0".
sequentially from "1".
: 05 is transmitted.
H
is transmitted.
H
, 04 , and 00 .
H H H
, 12 , and 00 .
H H H
1234"
1234".
and transmitted
H
and transmitted in
H
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