Reception With Interrupt Program (No Procedure) - Mitsubishi Electric MELSEC iQ-RJ71EN71 User Manual

Reception with interrupt program (no procedure)

Use the BUFRCVS instruction for receiving data with the interrupt program. The interrupt program is started when data is
received from the external device. It enables the reading of receive data to the CPU module.
The interrupt settings are required to use the interrupt program. ( Page 273 Interrupt Settings)
The following figure shows the receive processing for the fixed buffer No.2 area corresponding to the connection No.2.
'Initial status' (Un\G1900024.0)
'Open completion signal
(connection No.2)'
(Un\G1900000.1)
BUFRCVS instruction
In interrupt processing
 Normal completion of the initial processing is checked. ('Initial status' (Un\G1900024.0): On)
 A connection is established between the external device and the RJ71EN71 or the RnENCPU (network part), and normal completion of the connection No.2
open processings is checked. ( Page 378 TCP/IP Communications, UDP/IP Communications)
 The CPU module is requested to start the interrupt program, and data is received from the external device. ('Socket/fixed buffer reception status signal
(connection No.2)' (Un\G1900016.1): On)
 The interrupt program starts. The BUFRCVS instruction is executed, and the receive data length and receive data are read from the fixed buffer No.2.
('Socket/fixed buffer reception status signal (connection No.2)' (Un\G1900016.1): Off)
 Execution of the interrupt program ends, and execution of the main program resumes.
1 FUNCTIONS
76
1.5 Communications Using the Fixed Buffer
Initial processing Open processing
Ò
Ó
Cycle
Program Scan
Receiving data
Receiving data ACK
(TCP only)
Ô
END
Scan Interrupt processing
processing
Õ
Ö
Cycle
END
Scan
processing