Sqo Instruction

HI EVERY ONE I'M TRYING TO MAKE A LAB PROJECT CONTROLING FOUR SIGNAL LIGHTS USING A SQO INSTRUCTION ANY POINTERS THANK YOU IN ADVANCE

If your signal lights are supposed to be controlling vehicular traffic at a crossroad, and you have three colors , then you really have six lights. If you provide for left turns, then you have twelve lights.

Maybe its 1 in each of 4 directions flashing red.......

2 pointers

If AB,

Pointer #1) Beware of the length of the instruction. I.E. if the length is 9 then 10 words are used, words 0-9. Word zero is the initialization word, beware.

Pointer #2) The instruction basically moves a different value into the output word every time the instruction is pulsed.

Bonus pointer) go to http://www.ab.com/manuals/cp/#plc-5 and download the instruction set ref manual for the PLC5.

It sounds like your using AB. Using graph paper list all your outputs to be controlled the number can be unlimited but on your first SQO program limit it to 16 outputs. List them across the top of yor paper from 00-15. Now down the side of the paper list the steps in order keeping the very first step reserved for start-up only as refered to in an earlier reply. Now read the SQO instruction in the help section or refer to it in the manual and see if you can give it a try! Then after you get stuck ask a specific question! Genius is 95% effort!!

Sequencers

Oh I remember trying to figure out the dreaded sequencers.
It was even worse with the SLC100!
You can download an example Here

Hint download the PicknPlace_Sequencer.RSS

Sometimes you need to see how others have done it to really get a handle on what the manual is talking about.
Good luck!

The SQO only increments on a transition from low-to-high (just like a counter). Make sure that whatever conditions you have on the rung before the SQO go to "False" between transitions, but still allow the next step to have a continuous "True" path to the SQO.

And you thought you were already confused....

some sites that may be of interest for traffic control.
http://pbl.cc.gatech.edu/embed/16
http://pbskids.org/rogers/R_house/trafficautomatic.htm
http://www.bytronic.co.uk/traffic.htm
http://coel.ecgf.uakron.edu/grover/web/ee491/labs/SFC Traffic Light Controller.pdf
http://www.phy.ntnu.edu.tw/java/trafficControl/trafficControl.html
http://www.first.gmd.de/~espress/demo/
http://citeseer.nj.nec.com/3349.html
http://www.rflelect.com/trafficlight.html