Mitsubishi MELSEC Q Series Reference Manual page 392

(5) Commands
(6) Message wait
(7) Character area A
(8) Character area B
(9) Character area C
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A command is used to designate the type of access such as reading and writing
to be done from the external device to the applicable programmable controller.
The commands described in Sections 5.2 to 5.5 are designated by converting
them to 2-digit (hexadecimal) ASCII codes.
Message wait is a data value for generating delay time in response transmission.
Some external devices require a certain time to go into the receiving status after
sending a command.
This value designates the minimum time that the C24 must wait before sending a
result after receiving a command from an external device. The wait time should
be designated according to the specifications of the external device.
The wait time is designated in 10 ms units in the range from 0 to 150 ms, where
every 10 ms is converted to 1
(hexadecimal) from 0
H
The following shows an example of designating a message wait value.
(Example)
The message wait time is 100 ms
"A"
External device
side
Programmable controller CPU side
Start transmission after
100 ms or more
This data field, which is sent in ASCII code, is used to execute a read request
from the C24 to the programmable controller CPU. The contents of character
area A differ depending on the command sent from the external device. For
detailed explanations, refer to Sections 5.2 through 5.5.
This is the data that the C24 returns to an external device in response to a
request designated with a command. It is sent in ASCII code. The contents of
character area B differ depending on the command sent previously from an
external device. For detailed explanations, refer to Sections 5.2 through 5.5.
This data field, which is sent in ASCII code, is for issuing a command to the C24
to execute a write request on the programmable controller CPU.
The contents of character area C differ depending on the command sent from the
external device. For detailed explanations, refer to Sections 5.2 through 5.5.
5 WHEN COMMUNICATING USING THE A COMPATIBLE 1C FRAMES
in order to obtain a 1-digit ASCII code
H
to F (0 to 15).
H
Message wait (100 ms)
Wait time is not
necessary
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