Created Date: July 12,2000

Created by: Bob Kobetsky

Special relays SP3-SP6 provide pulse trains.

I need to drive a counter at least at a 10 ms. period so I'm thinking of using a free running fast timer (TMRF)resetting itself after a count of one.

Is there a better way to generate a 5 or 10 ms. pulse train?

Thanks,

Bob

Created Date: July 13,2000

Created by: Mike McClanahan

Bob sorry it took so long to get a reply to you but I had to research this out a little. In the catalog on page 1-25 they discuss the Timed Interrupt Mode of operation and they state that you can interrupt the PLC on 5 MS intervals. If you interrupt the PLC on 5 MS intervals and turn on a output on one scan and then turn it off on the next interrupt you will get 10 MS pulses.

Mike

Created Date: July 13,2000

Created by: Russ

Hi Bob,

I agree with Mike - have you looked at using the HSIO Mode 40 and an interrupt routine? Page 3-44 to 3-48 of the DL05 User Manual explains the details. 5-10 ms is tough to get reliably since it is close to the average scan time of the logic, but using the hardware counter, interrupts and immediate instructions should get you what you need. Just curious, but are you driving any real outputs or reading inputs with the same time constraints?

Created Date: July 13,2000

Created by: Bob Kobetsky

Thank you, Mike and Russ, for the tips. I'll try what you suggested and compare it to my first idea of using a free running fast timer.

I'd guess that the timer method might add some part of scan time to each 10 ms. reset so it may not be very accurate.

Regarding I/O, they are all in the 100 ms. minimum area.

Thanks again,

Bob