Mitsubishi QJ71MB91 - Page 120

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5.2 Master Function
5.2.1 Automatic communication function
5
FUNCTIONS
(a) The Request interval timer times out, and then restarts
The Request interval timer represents the interval between any successive
request message transmissions in the automatic communication function.
( Section 7.2.1 (3))
(b) Request message is issued to the station
Request messages are issued at the timing shown in the above (a).
(c) The Response monitoring timer/Broadcast delay starts
The Response monitoring timer is used to monitor the time taken between a
response message transmission from QJ71MB91 and reception of a response
message from a slave.
The Broadcast delay monitors the time interval between transmissions when
request messages are broadcast.
The Response monitoring timer/Broadcast delay starts when a request message
is sent.( Section 7.2.1 (4))
Figure 5.3 Request interval timer operation
Figure 5.4 Response monitoring timer/Broadcast delay operation
Request interval timer times
out, and then restarts
Master
(QJ71MB91)
Request interval timer
Receiving
response
message
Request
message
processing
Request
message
Request
message
processing
Response
message
Slave
Receiving
response
message
Request
message
Response
message
Start Response monitoring
timer/Broadcast delay
Request interval timer
Request interval timer
Response monitoring timer Broadcast delay
Master
(QJ71MB91)
Slave 1
Slave 2
Slave 3
Request
message
processing
Response
Message
Receiving
response
message
*2
Request
message
*1
Request
message
Request
message
processing
Request
message
processing
Request
message
processing
Request
message
*1 When request message is addressed to station No.1 to 247
*2 When request message is addressed to station No.0 (Broadcast)