Mitsubishi MELSEC-Q Series User Manual page 98

4
FUNCTIONS
(3) Message communication functions
Remark
(4) Message communication example
Q06CCPU-V
User program
ret = QBF_SEND();
or
ret = mdSend();
4
- 18
4.4 MELSECNET/H Module Access Function
4.4.1 Message communication
The following functions are available for message communication.
Function
Function
name
QBF_SEND
Message
transmission
mdSend
QBF_RECV
Message
reception
mdReceive
* 1 MELSEC data link functions are not available for the Q06CCPU-V-B.
Refer to Chapter 10 for details of the bus interface functions and MELSEC data
link functions.
The following gives a message communication example.
1) The Q06CCPU-V sends a message using the message sending function of the
user program.
2) Station No.4 sends the message to the target station storage channel 5 (logical
channel 5) of Station No.5 using its Channel 3 according to the message
sending function of the user program.
3) The Q06CCPU-V (other station) automatically checks the message stored in
Station No.5, and stores it into the internal buffer for message reception.
4) The Q06CCPU-V (other station) reads the message from the internal buffer for
message reception using the message receiving function of the user program.
MELSECNET/H
module (Station No.4)
Channel 1
1)
Channel 2
Channel 3
2)
Channel 4
Channel 5
Channel 6
Channel 7
Channel 8
Network No.1
Figure 4.13 Message communication example
Table4.6 Message communication function list
Sends a message to the other station via a MELSECNET/H
*1
module. (Equivalent to the SEND instruction)
Receives a message from the other station via a
*1
MELSECNET/H module. (Equivalent to the RECV instruction)
MELSECNET/H
module (Station No.5)
Logical channel 1 (Channel 1)
Logical channel 2 (Channel 2)
Logical channel 3 (Channel 3)
Logical channel 4 (Channel 4)
Logical channel 5 (Channel 5)
Logical channel 6 (Channel 6)
Logical channel 7 (Channel 7)
Logical channel 8 (Channel 8)
Description
Q06CCPU-V
(other station)
Internal buffer
User program
for message
ret = QBF_RECV();
reception
4)
or
1st
ret = mdReceive();
2nd
3)
127th
128th