Can anyone tell me what instruction (and how to) compare or switch a bit/output for each position of the sequencer, i.e. i know i ignor position 0, but then want to energise say output 1 when seq is at position 1, output 2 when in position 2 etc.
First you need to understand how a Sequencer works. It is a simulation of the old mechanical drum switch. When the drum turns, it has "knobs" (protrusions) on it that activates output switch contacts. The outputs and the sequence of the outputs are strictly defined and pre-set ahead of time. You can only control WHEN the drum turns (steps to next output), not how the outputs are arranged (once they are set). That is why a sequencer is only useful for an operation that is well-defined, well-known, and once set, the sequence never varies.
For the SQO instruction, you can manually set the outputs ahead of the operation by opening the Data Table (B3 in this case) and setting one-or-more bits to "1" in a series of words (16-bit collection). This series of words is the "pattern" that the sequencer uses to determine which Outputs to turn on on each Step. In my previous example, with Start Position #B3:1, and using Words B3:2 to B3:9 (Length of 8 words):
To turn on Output O:2/0 in Step 1, set B3:2 = 0000000000000001 (decimal 1).
To turn on Output O:2/1 in Step 2, set B3:3 = 0000000000000010 (decimal 2).
To turn on both Outputs 0 and 1 on Step 3, set B3:4 to 0000000000000011 (decimal 3).
To turn off all Outputs in Step 4, set B3:5 to 0000000000000000 (decimal 0).
To turn on Output O:2/2 in Step 5, set B3:6 = 0000000000000100 (decimal 4). You get the idea.
Once Step 8 (or whatever you set Length) is done, the sequencer goes back to Step 1 and repeats the cycle.
To prevent any bit from being capable of turning on, set a 0 in the "Mask" for that output.
The ahead-of-time sequencer set-up operation can be done automatically by the PLC, usually on the First Scan by using S:1/15 to move the correct value to each word of the SQO sequencer. A PLC sequencer's steps can actually be re-defined while operating, but that job is not recommended for the beginner.