What I want to know. Is this homework? OP looks like homework to me.

No it's part of my project

Why do I believe this thread goes back to your questions in this open thread? In

All of this would likely go better if you kept everything in a single thread. People would then understand your objective and better help you.

yes, you're correct but I did not want to mix all things in one. I have divided the project into many small parts. That's why I created a new thread

I am following that thread but I am researching on it. Still I think I have to understand many things

 

I have divided the project into many small parts. That's why I created a new thread

hi champ1,
I would recommend that you do not create a new thread for each sub topic of your project.
E
Mod Note:

 

hi champ1,
I would recommend that you do not create a new thread for each sub topic of your project.
E
Mod Note:

Then I would like to continue old thread. Can you merge it in a single thread

 

OK, back on track and Thanks Eric.

Several post back I showed you how to interface to a RS232 port adapter (USB to RS 232) I even provided a sample program with illustrations of the port pins. In addition I provided a link to programming in C# since you mentioned C# connection and reading the DIO pins of RS232. The link for Serial Comms in C# for Beginners is well written and includes examples of reading the DIO pins of a RS232 port.

As to sensing the cartons or product you start by thinking about what type sensor, for example reflective or break a beam and distance. You will be writing your software around the sensor output going either high or low when product is detected and consider distance between sensor and object. You choose a sensor based on a collection of variables.

Somewhere way back in the beginning I suggested you sit down with a sharp pencil and blank sheet of paper and layout your project. You look at where the system will be installed.

Something else I always found useful is when considering a project component (hardware) I would call an applications engineer from the company I planned to buy the product from and get their ideas and suggestions. You call the company who manufactures a product you have interest in and request to speak with an applications engineer. You describe your project and get their views. That is how it is done.

I asked numerous times how or where you plan to store your collected data? I also do not see where the same product would have different barcodes? Both of those should be at the very beginning of the project.

Ron