CPU
S
pecifications
and
Operation
4--16
CPU Specifications and Operation
DL105 PLC User Manual, 3rd Edition
The I/O response time is longest when the input changes just after the Read Inputs
portion of the execution cycle. In this case the new input status does not get read until
the following scan. The following diagram shows an example of the timing for this
situation.
Solve
Program
Read
Inputs
Write
Outputs
Solve
Program
Scan
Solve
Program
Field Input
Input
Off/On Delay
CPU Reads
Inputs
Output
Off/On Delay
I/O Response Time
Scan
Solve
Program
CPU Writes
Outputs
In this case, you can calculate the response time by simply adding the following
items:
Input Delay +(2 x Scan Time) + Output Delay = Response Time
Normal Maximum
I/O Response
Summary of Contents for DL105
Page 2: ...DL105 PLC User Manual Manual Number D1 USER M...
Page 308: ...1B DL105 Error Codes In This Appendix Error Code Table...
Page 314: ...1C Instruction Execution Times In This Appendix Introduction Instruction Execution Times...
Page 324: ...1D Special Relays In This Appendix DL105 PLC Special Relays...
Page 327: ...1E PLC Memory In This Appendix DL105 PLC Memory...