Mitsubishi QCPU (Q Mode), Руководство пользователя

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MELSEC-Q
4 SEQUENCE PROGRAM CONFIGURATION AND EXECUTION
CONDITIONS
4.7 I/O Processing and Response Lag
In the direct mode, the batch communication with I/O modules is performed before
sequence program operation starts.
By creating a sequence program with direct access I/O, I/O processing can be
performed in a direct mode to communicate with I/O module at execution of each
instruction in the sequence program.
For details on direct access I/O, see Section 10.2.1 and 10.2.2, respectively.
4.7.1 Refresh mode
(1) Definition of refresh mode
With the refresh mode, batch communication with the I/O modules is performed
before the sequence program operation starts.
(a) Batch reading of the input module ON/OFF information is executed in the
High Performance model QCPU's internal input device memory when
sequence program operation starts. This ON/OFF data (in the input device
memory) is then used for processing when a sequence program is
executed.
(b) The processing result of the output (Y) sequence program is output to the
High Performance model QCPU's internal output device memory, and
batch output of the ON/OFF data (in output device memory) to the output
module is executed when sequence program operation starts.
Input
module
Output
module
GX Developer
input area
For device
memory
output (Y)
CPU (operation processing area)
1)
2)
4)
5)
High Performance model QCPU
At input
refresh
At output
refresh
3)
Input (X)
device
memory
Area for
communication
with input module
1) At input
refresh
2
Y20
Y22
X0
1
Network
module
Network
module
3
Remote input
refresh area
• Input refresh:
Input information is read in a batch 1) from the input module before sequence
program operation starts, and is stored in the input (X) device memory by an OR
operation in the peripheral device input area.
• Output refresh:
Data in the output (Y) device memory is output in a batch 2) to the output module
before sequence program operation starts.
• When an input contact instruction has been executed:
Input information is read 3) from the input (X) device memory, and a sequence
program is executed.
• When an output contact instruction has been executed:
Output information is read 4) from the output (Y) device memory, and a sequence
program is executed.
• When an output OUT instruction has been executed:
The sequence program operation result 5) is stored in the output (Y) device memory.
Fig.4.7 I/O Information Flow in Refresh Mode