Data Sending/Receiving - Mitsubishi Electric Melsec Q Series User Manual

4 WHEN THE Q/LCPU ACCESSES THE PROGRAMMABLE CONTROLLER
OF ANOTHER STATION USING THE DATA LINK INSTRUCTION

4.5 Data Sending/Receiving

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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 programmable controller 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 programmable
controller CPU with which communication is being performed to enable
receive data reading to the programmable controller CPU.
To start the interrupt program, set the parameters on the following screens of
a programming tool.
1) "Network Parameter Ethernet Interrupt Settings" screen
Set the control number (SI) on the Ethernet module side when an
interrupt request is made to the programmable controller 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 the
User's Manual (Basic).
POINT
(1) To start an interrupt program, the following settings with a programming tool
and interrupt permission in a sequence program are required.
• Interrupt settings in the network parameter screen and intelligent function
module interrupt pointer setting
• 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 one of the programs to read receive data.
Received data cannot be read with the main program when the settings to read
receive data with an interrupt program are being configured using a
programming tool.
MELSEC-Q/L
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