Manual

4: SOFTWARE SPECIFICATIONS
SX5L COMMUNICATION TERMINAL USER’S MANUAL 4-9
Heartbeat Transmission (Periodical Transmission)
When the status at any input terminal does not change, this functional block sends the output network variable repeatedly
at intervals designated by nciMaxStsSendT1[0] to [3]. When the nciMaxStsSendT1[0] to [3] value is 0, the heartbeat
transmission is disabled.
The configuration type of nciMaxStsSendT1[0] to [3] is SNVT_elapsed_tm (day, hour, minute, second, millisecond).
When a value over 12 hours is set, the interval is designated as 12 hours 00 minutes 00 seconds. The millisecond value has
no effect.
Input Network Variables vs. Output Pulse
Depending on the statuses of input variables nviDO and nviOVR, a start or stop output pulse is generated or suppressed.
For DIO[0], the following tables summarize the relationships of input variables nviDO[0] and nviOVR[0] with start or stop
output pulse generation from output terminal 0 or 1, respectively. For DIO[1] through DIO[3], start and stop output pulses
are generated from output terminals 2 through 7 similarly.
(1) While nviOVR[0] is off
When nviDO[0] receives an ON signal while nviOVR[0] is
off, this functional block sends a start 0 pulse (pulse width
approximately 1 second) from output terminal 0. When
nviDO[0] receives an OFF signal, this functional block sends
a stop 0 pulse (pulse width approximately 1 second) from out-
put terminal 1.
Note: Once nviOVR[0] has received an OFF (or ON) signal, the internal nviOVR[0] status remains off (or on) until nviOVR[0]
receives an ON (or OFF) signal. Similarly, once nviDO[0] has received an OFF (or ON) signal, the internal nviDO[0] status
remains off (or on) until nviDO[0] receives an ON (or OFF) signal.
(2) While nviOVR[0] is on
While nviOVR[0] is on, nviOVR[0] overrides nviDO[0]. Con-
sequently, this functional block does not send a start or stop
pulse even when nviDO[0] receives an ON or OFF signal
while nviOVR[0] is on.
(3) While nviDO[0] is on
When nviOVR[0] receives an ON signal while nviDO[0] is
on, this functional block sends a stop pulse (pulse width
approximately 1 second) from output terminal 1. When
nviOVR[0] receives an OFF signal, this functional block
sends a start pulse (pulse width approximately 1 second) from
output terminal 0.
(4) While nviDO[0] is off
When nviOVR[0] receives either an ON or OFF signal while
nviDO[0] is off, this functional block sends a stop pulse
(pulse width approximately 1 second) from output terminal 1.
nviOVR[0] Status nviDO[0] Received Data Pulse Output
OFF
Receive ON signal Sends a start 0 pulse from output terminal 0
Receive OFF signal Sends a stop 0 pulse from output terminal 1
ON Receive either ON or OFF signal No output
nviOVR[0] Received Data nviDO[0] Status Pulse Output
Receive ON signal Either ON or OFF Sends a stop 0 pulse from output terminal 1
Receive OFF signal
ON Sends a start 0 pulse from output terminal 0
OFF Sends a stop 0 pulse from output terminal 1
Start 0 Pulse (Output terminal 0)
nviDO[0] (state) Received Data
Stop 0 Pulse (Output terminal 1)
Start 0 Pulse (Output terminal 0)
nviDO[0] (state) Received Data
Stop 0 Pulse (Output terminal 1)
Start 0 Pulse (Output terminal 0)
nviOVR[0] (state) Received Data
Stop 0 Pulse (Output terminal 1)
Start 0 Pulse (Output terminal 0)
nviOVR[0] (state) Received Data
Stop 0 Pulse (Output terminal 1)