Sharp JW-20CM User Manual page 43

① Operational synchronous
When more than one JW-20CM is installed while using the remote I/O function, set only one module
as "operational synchronous." When a link module ZW-10CM or JW-10CM is used for remote I/O, the
JW-20CM should be set as "operational asynchronous."
a. When operation interval (one scan) of the master station PC is longer than data transfer
time of the remote I/O:
I/O processing
at PC side
PC scan cycle
b. When operation interval (one scan) of the master station PC is shorter than data transfer
time of the remote I/O:
I/O processing at PC side
PC scan cycle
※ A waiting time is provided after the PC process to match with end timing of the data transfer
process of the remote I/O so that the remote I/O can synchronize with the PC scan cycle.
② Operational asynchronous
The special I/O module can not be used with the remote I/O slave module as the special I/O module
cannot synchronize with the master station PC for data exchange.
a. When operation interval (one scan) of the master station PC is longer than data transfer
time of the remote I/O:
Same as operational synchronous above.
b. When operation interval (one scan) of the master station PC is shorter than data transfer
time of the remote I/O:
I/O processing
at PC side
PC scan cycle
Data exchange with the buffer memory
I/O processing at PC side
PC operation time
Remote I/O data
transfer processing
Data exchange with the buffer memory
I/O processing at PC side
PC operation time
Remote I/O data transfer processing
Data exchange with the buffer memory
I/O processing at PC side
PC operation time
Remote I/O data transfer processing
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Waiting time
PC operation time
Remote I/O data transfer processing
Remote I/O data
transfer processing
PC operation time
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