Mitsubishi Electric MELSEC iQ-R Series User Manual page 332

Ex.
When ASCII-BIN conversion is performed
Target device
Head data
1 2
31 32
H H
■Data reception using user frames
• C24 checks the reception of the user frame (start frame and final frame).
• C24 deletes (removes) the additional code designation data from an arbitrary data portion when a transparent code for
receiving is specified.
• C24 calculates the sum check code when a sum check code is designated in a user frame (final frame).
• C24 stores the arbitrary data portion in the receive area on the buffer memory.
When ASCII-BIN conversion is designated, C24 converts it to binary code data and stores in the buffer memory.
• C24 issues a reception data read request to the CPU module when the receive end code/data equivalent to the receive end
data quantity is stored during reception of an arbitrary data portion, or when a user frame (final frame) is received.
■Transmitting data using user frames
• C24 transmits data to be sent (an arbitrary data portion of a transmission message), which is designated by the user frame
or CPU module, in the order specified by the user.
• When ASCII-BIN conversion is designated, C24 converts the data in the applicable range to ASCII code data and transmits
it.
In addition, it adds the additional code data immediately before the transparent code/additional code data when transmitting
the data in the applicable range, and transmits it when a transparent code for sending is specified.
• C24 notifies the CPU module of the transmission normal (abnormal) completion once transmission for the send data
quantity has been completed.
C24
Target device
Data
transmission
Data
reception
Check and
delete user
frames
The figure above shows how C24 processes the data to be sent/received when the data sending/receiving function using user
frame, the ASCII-BIN conversion function, and/or the data send/receive function by transparent code designation are enabled
and disabled.
Use this information as a reference to select the method to send/receive data for data communication with a target device.
16 TRANSPARENT CODES AND ADDITIONAL CODES
330
16.3 Handling Transparent and Additional Codes for Nonprocedural Protocol Data Communication
(Communicating in an arbitrary format)
Arbitrary data
D
L
E
0 2 3 A B C
30 32 33 10 41 42 43
H H H H H H H
Transparent code
(For 41H)
Additional code
(For 10H)
(Transparent code designation) (Sum check code designation)
No
Adding
additional
Yes
code
No
Delete
Yes additional
code
(Arbitrary data section only)
Send
Receive
(ASCII-BIN conversion designation)
No
ASCII-BIN
Calculating sum
conversion of
check code using
Yes
transmission
user frames
data
For Output count designation
No
No
Calculate and
check
Yes Yes
sum check code
using user frames
C24
Buffer memory (transmission area/reception area)
(H) (L)
(0002H)
00H , 02H
(0212H)
02H , 12H
(BC3AH)
BCH , 3AH
(The data count is in word units)
No
Yes
ASCII-BIN Check reception
conversion of complete code
arbitrary data and received
section data count
Transmission data
count/Receive
data
count
Transmission
data/
receive data
Buffer memory
Data designated
in the transmission
frame No.
designation area
Data stored
in the
reception
area