Mitsubishi QJ71E71-100 Series, Руководство пользователя

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MELSEC-Q
4 WHEN THE QCPU ACCESSES THE OTHER STATION PLC USING THE
DATA LINK INSTRUCTION
4.5 Data Sending/Receiving
This section explains the arbitrary data sending/receiving function, instruction format
and programs using the data send/receive instructions (SEND, RECV and RECVS
instructions).
(1) The SEND, RECV, and RECVS instructions are used for sending and receiving
arbitrary data to/from the PLC CPU with which communicate is being performed.
(2) Data sending is performed using the SEND instruction and data receiving is
performed using the RECV or RECVS instruction.
The RECV instruction and the RECVS instruction are used differently as follows.
(a) The RECV instruction is used in the receiving processing in the main program.
The main program reads from the RECV instruction executing request area in
the buffer memory and executes the RECV instruction using a switch from off
to on of a bit corresponding to the data receiving channel number as a trigger.
(b) The RECVS instruction is used in the receiving processing in an interrupt
program.
An interrupt program is started when data is received from the PLC CPU with
which communication is being performed to enable receive data reading to
the PLC CPU.
In order to start the interrupt program, set the parameters on the following
screens of GX Developer.
1) "Network Parameters Ethernet Interrupt Settings" screen
Set the control number (SI) on the Ethernet module side when an
interrupt request is made to the PLC CPU from the Ethernet module.
2) "Intelligent function module interrupt pointer setting" screen
Associate the control number (SI) set in the "Ethernet Interrupt Settings"
above with the interrupt pointer (Ixx) used in the sequence program.
The settings on the two screens above are the same as when received data is
read by an interrupt program in the fixed buffer communication.
For details on the settings and setting method on these screens, see Section
7.3.2 of the User's Manual (Basic).
POINT
(1) In order to start an interrupt program, the following settings with GX Developer
and interrupt enable by the sequence program must be required.
• "Network parameters Ethernet interrupt settings" and "Intelligent function
module interrupt pointer settings" with GX Developer.
• Create interrupt enable/disable programs in the main program in order to
start an interrupt program.
Use the EI, DI and IMASK instructions for this.
(2) In cases where receive data is read on the same channel, the main program for
reading receive data and the interrupt program for reading receive data can not
be used together. Please use either program to read receive data.
In order to read receive data with the interrupt program, when the setting
corresponds to GX Developer, the main program can not be used to read
receive data.