Urgent

i am a student. i have one question do not understand. Please someone help me.
Describe these internal features of PLC in detail:
CPU
ALU
Opto-isolators
Flags
shift registers
typical internal input and output circuits.

Also describe teh operational characteristics of the flow of data within the PLC including:
Scanning
Continuous updating
Mass I/O copying

Please someone can help me. This is urgent. Many thanks

qq416 said:

i am a student. i have one question do not understand. Please someone help me.
Describe these internal features of PLC in detail:
CPU
ALU
Opto-isolators
Flags
shift registers
typical internal input and output circuits.

Also describe teh operational characteristics of the flow of data within the PLC including:
Scanning
Continuous updating
Mass I/O copying

Please someone can help me. This is urgent. Many thanks

Click to expand...

internal features are wires, boards, solder, battery, chips.
the flow of data is by stuff coming in on the inputs and going out on the outputs.

I would think you would read your textbook or at least try harder. If this material is too much for you, please consider something easier in learning (like - Do you want fries with that?)

If you click the link for "Learn PLCs" at the top of this forum, you should be able to find answers for almost all of your questions within a few minutes.

What class or topic is this question for?

$

This should help...


http://www.ebaumsworld.com/retro.html

I counted more than one question.

http://www.freestudy.co.uk/plc/

For additional information about how highly some members of this forum regard HNC students looking for a free ride through their coursework, use "HNC" as keyword for a search of this site.

qq416 said:

i have one question do not understand.

Click to expand...

Dang, you're good. I have several questions I don't understand on a daily basis! I usually have just as many answers I don't understand.

qq416 said:

This is urgent.

Click to expand...

Not to me.

I have lots of answers, I just can't find any questions for them.

Hold it guys...I can answer this one.

Ok first of all the internal features of the CPU- Usually a small green board with lots of assorted IC chips and other misc. components soldered to it. ALU- Sorry don't have a clue what that one is. Opto-Isolators- things that isolate the optos. Flags- every country has one, as do all the states here in the US. Shift registers- What they did when they remodeled Walmart last year. Typical input and output circuits- N.O. pushbutton and a lightbulb. How am I doing so far??

ALU = American Liberties Union.... The conservative branch of the ACLU. Obviously the omission of the C implies that it is the American Uncivil Liberties Union.

ALU = arithmetic logic unit

CPU is Central Processing Unit; it is the microprocessor that takes all the information and acts upon it

ALU is arithmatetic logic unit; performs arithmatetic computtations.

Opto-isolators; opto is a reference to light which means it uses light to transfer a signal..i.e. isolate the electrical, from the destination.

Flags; Just think about a white flag used in war etc, it is a signal to denote attention.

shift registers: a register (or word) holds bits for a purpose. These can be shifted, right or left, to accomplish a purpose. An example is tracking product on a conveyor..shift a bit each time the product passes a set point.

typical internal input and output circuits; Each PLC has internal bits, the denotation depends on the PLC. They are the equivalent of inputs and outputs BUT there are no physical connections to access them.

ToddM said:

ALU- Sorry don't have a clue what that one is.

Click to expand...

ALU - Aluminum. The PLCs are getting a lot lighter and look at the price of copper:nodi: