Mitsubishi LJ61BT11 User Manual page 176

(4) Data flows in synchronous and asynchronous modes
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The data flows in both the synchronous and asynchronous modes are explained
using examples of communications between the master station and remote I/O
stations.
(a) Data flow in the asynchronous mode
I: Delay time due to response delay of remote I/O station
II: Delay time of transmission from the remote I/O station to the master
station
III: Delay time from reception by the master station to storage in the buffer
memory
IV: Delay time until the master station's information is refreshed in the
programmable controller CPU
8 FUNCTIONS
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