Reading analog inputs of Micrologix 1100

Look on p.157 of

You don't get as many configuration options on the built-in I/O as the expansion modules.

Any particular reason for using a MicroLogix? (As opposed to flex or compact?)

Thank you for your reply. This is gonna sound stupid but I already know that the analog inputs are available on I:0.4 and I:0.5. What I can't figure out is how to read in all 10-bits at once for comparisons. Can I just specify I:0.4 in a compare instruction? Usually, in case of relays you specify something like I:0/0 to read in a bit but I don't know how to read in multiple bits at the same time. Also, how do I configure the analog inputs to be read in as raw values and not the PID scaled values? We're using an expansion card for analog outputs and I've already configured them to be output as raw values but I can't figure out how to do this for the built-in channels.

As for the choice of MicroLogix over other PLCs, I have no idea. Someone else was originally supposed to do this; but then the management figured out that he wouldn't have much time and I'm low enough in the chain that all this was thrown onto my plate :-). This is not what I work on usually, I develop motor control algorithms using Matlab and Simulink. I've learned about PLCs in school about 5 years ago and then I started working on this last week. Do you know of any good tutorials or demos that are specific to the MicroLogix PLC family? That would be really helpful to me at this point.

Thanks, Ashish.

Yeah, you can address the whole word or just the bits.

In the PLC5 & SLC (I'm guessing in MicroLogix, too, but I haven't tried it), you can get to hidden values in structured data files (message file) by COP from the message file to an array of INT. Then mess with the INTs & COP them back.

You shouldn't have to worry about that; just address the word.

Sorry, I don't know any good tutorials; if you've got the hardware, just plug it in and see if it does what you expect. Wire the outputs to the inputs & punch in values to the outputs while online. Hang a meter on it & see if it's what you expect. Should be good for at least a sanity check, though it's not going to tell you if performance is sufficient.