Omron CJ Series Operation Manual page 190

5 Operation
CPU Cycle
Slave I/O data refresh
PROFIBUS Cycle
Slave I/O data refresh
T
IN
TRUE
T
IN
T
PB,Cyc
T
M,Proc
with increasing I/O data size.
T
M,Rrf
T
CPU,Cyc
T
CPU,Rf
T
OUT
The total I/O response time is the sum of all components:
T = T + 4*T
IO IN
Note The calculation assumes the presence of only one Master Unit on the PROFIBUS network.
 PROFIBUS DP Cycle < CPU Cyclic Refresh
The figure below shows the timing in case the PROFIBUS DP cycle < CPU cyclic refresh.
Instruction
CPU Cycle
Execution
Slave I/O data refresh
PROFIBUS Cycle
Slave I/O data refresh
T
IN
TRUE
5-38
Instruction Instruction Instruction
Execution Execution Execution
T T
PB,Cyc PB,Cyc
T + T
M,Proc
Slave device Input TRUE (FALSE) delay.
PROFIBUS I/O data exchange cycle time (See Appendix A Bus Parameters)
I/O Processing time in the Master Unit. Minimum value is 430 s but may increase
Master request cyclic refresh until actual start of cyclic refresh.
CPU cycle time.
CPU cyclic refresh time.
Slave device Output TRUE (FALSE) delay.
+ 2*T + T
PB,Cyc M,Proc M,Rrf
Instruction
Execution
T T
PB,Cyc PB,Cyc
T + T
M,Proc M,Rrf
CJ-series PROFIBUS Master Unit Operation Manual for NJ-series CPU Unit (W509)
Instruction Instruction Instruction
Execution Execution Execution
T T
CPU,Cyc CPU,Cyc
T
M,Proc
T
M, Rrf CPU,Rf
+ 2*T + T + T
CPU,Cyc CPU,Rf
Instruction Instruction
Execution Execution
T T
CPU,Cyc CPU,Cyc
Instruction Instruction
Execution Execution
T T
PB,Cyc PB,Cyc
T
OUT
OUT
Instruction
Execution
T T
PB,Cyc PB,Cyc
T
T
M,Proc
OUT
T
CPU,Rf
TRUE
TRUE