SQO and SQC Problems for RSLogix 500


Join Date
Feb 2008
I am currently doing a project that involves two different robo cylinders. For each robo cylinder the outputs (programmed under the SQO instruction) is for the actual moving action of the cylinder, and the inputs (programmed under the SQC instruction) is for the completed command after each output has been completed.

What I'm having trouble with, is which instruction must be activated first (SQO-Outputs or SQC-Inputs) and how to have each instruction to be on one at a time. For example, when the SQO is on...the SQC should be off and vice versa.
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here is the program for the SQO and the SQC...we need to know how to make the SQO and SQC instructions to work in sync with each other.

OK I'm looking at this program but I need some info first what output patterns do you need for each step? I take it you want to goto the next step after the SQC compares correctly goto next step on the SQO then compare when FD is active goto next step on SQO ? I also need the data for n7:0 and n7:1
couple of problems I see so far
n10:0 is invalid valid ranges are 0 to 7 only one available appears to be
both destinations on SQO and SQC report as unconfigured I/O addresses
still working on the control issues evidently you did not try to verify the rungs.oou

Here is a working program sqc to sqo relation when you first run the program trigger input I:0/0 you will see output 1 come on
I did not have the sequence steps to apply to the two n7 data files
here is the sequence:

There are two cylinders and they are named RCP2 and RCP
Home Position for RCP2 : O:2/4
Start Signal : O:2/0
Command Position 1 : O:2/1
Command Position 2 : O:2/2
Command Position 3 : both O:2/1 and O:2/2 have to be ON
Complete Home Position : I:1/3
Complete Position 1 : I:1/0
Complete Position 2 : I:1/1
Complete Position 3 : I:1/2

Home Position for RCP : O:2/12
Start Signal : O:2/8
Position 1 : O:2/9
Position 2 : O:2/10
Position 3 : both O:2/9 and O:2/10 have to be ON
Complete Home Position : I:1/7
Complete Position 1 : I:1/4
Complete Position 2 : I:1/5
Complete Position 3 : I:1/6

With these addresses, here is the sequence:
1. Home Position for RCP2 and RCP
2. Start signal and RCP2 Position 1
3. Complete Position 1 for RCP2
4. RCP Position 3 and Start signal
5. RCP Position 2 and Start signal
6. RCP2 Position 2 and Start signal
7. RCP2 Position 3 and Start signal
8. RCP Position 1 and Start signal
9. RCP Position 2 and Start signal
I'm not going to have time to set up your bit patterns for the SQC, SQO masks. to answer your earleir question as to which comes first you will need to satisfy SQC first in order to activate SQO according to the sequence in your program. As I do not know how much knowledge you have on the instructions both SQO and SQC will refer to a data table for the inputs/outputs if you right click the instruction you should be able to see edit special to get to those tables. or you can write your patterns there directly. Good Luck If you have further questions feel free to ask someone will be able to help you if I cannot find time this week

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