Thank you very much for answering.
If I have said about the dollar protocol, it has been because, the one who sold me the scale insisted many times. It is true that I have not found much information about this protocol either, and, however, I did find more documentation on connecting Access with a serial port through an RS232 cable.
As for the forum you mention, I had already visited it. I have downloaded both databases and Excel to test it on the computer, but neither of them does anything. I have asked my brother, who is a computer technician, if it was necessary to install some kind of driver for the scale and he told me that Windows should instal it by itself. I have sent him a screenshot of the COM devices and he has replied that in principle it is fine. But even with those, I am not able to get any kind of data from the scale.
What I am going to do tomorrow is ask where I bought the cable today if they could look at my computer, so that if they tell me that it does not connect, they will give me my money back. Later, what I would do is buy the cable directly from the one who sold me the scale, since he has an identical one for his business and is using that cable.
As I say, thank you very much. I'm leaving this thread open in case I have anything else to ask.
Good night.