Omron DRT2 SERIES DEVICENET SLAVES - OPERATION MANUAL 04-2008 Operation Manual page 471

Remote I/O Communications Characteristics
Communications
Time for each Slave
Output Slaves with up to 8
Bytes of Output
Input Slaves with up to 8
Bytes of Input
Mixed I/O Slaves with up
to 8 Bytes of I/O
450
= Σ (communications time for each Slave)
T
RM
+ MULTIPLE I/O TERMINAL processing time
+ Explicit message communications time
+ COS/Cyclic connection communications time [ms]
+ 0.01 × N + 1.0 [ms]
Communications time for each Slave:
Time required for each Slave. (Refer to pages 450 to 451.) Σ (commu-
nications time for each Slave) is the total of the processing of each
Slave in the Network.
MULTIPLE I/O TERMINAL processing time:
3.5 [ms]
Only when Slaves with input, output or mixed I/O of more than 8 bytes
exist.
Explicit message communications time:
0.11 × T + 0.6 [ms]
B
Added as delay time when explicit message communications (send or
receive) are used.
T : Constant (500 kbps: T
B
COS/Cyclic connection communications time:
(0.05 + 0.008 × S) × TB × n [ms]
Added as delay time when COS/Cyclic connection is used for com-
munications.
S: Total size (bytes) of the COS/Cyclic connection's input size and
output size.
n: Number of nodes for which COS/Cyclic connections occur at the
same time during one communications cycle.
N: Number of Slaves
The communications time for each Slave is the time required for communica-
tions to be performed with a single Slave.
The following equations show the communications time per Slave (T
each kind of Slave Unit.
T = 0.016 × T × S
RT B OUT1
S : The number of Output Slave output words
OUT1
T : The baud rate (500 kbps: T
B
= 8)
T = 0.016 × T × SOUT1 + 0.06 × T
RT B
S : The number of Input Slave input words
IN1
T : The baud rate (500 kbps: T
B
= 8)
T = 0.016 × T × (S
RT B OUT2
S : The number of Mixed I/O Slave output words
OUT2
S : The number of Mixed I/O Slave input words
IN2
T : The baud rate (500 kbps: T
B
= 8)
= 2; 250 kbps: T
B
+ 0.11 × T + 0.07 [ms]
B
= 2; 250 kbps: T
B
+ 0.05 [ms]
B
= 2; 250 kbps: T
B
+ S ) + 0.11 × T + 0.07 [ms]
IN2 B
= 2; 250 kbps: T
B
Section 8-1
= 4; 125 kbps: T = 8)
B B
) for
RT
= 4; 125 kbps: T
B
= 4; 125 kbps: T
B
= 4; 125 kbps: T
B
B
B
B