From a communications chat computer

Guidance Questions

Give you some wire, and a small light bulb, can you let the computer light it?

How to protect the loss of data bit in communication?

(This technique is mostly done a few years ago, and the details of the premises may not be very accurate.)

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For interface, different system different platform has different interface, different virtual way, we first take RS232 example, because of the same hardware parameters, whether Linux or Windows this piece is consistent.

For RS232 programs, they tend to only care about data, so they tend to focus on only 2 or 3 of them. (In fact, some do hardware also he is only 235, the specific definition can go to the MSDN document or RS232 definition)

It is well known that this parameter is very conspicuous--frequency, why is the frequency--note the title ha, we commonly used 9600 is not. The current calculation of the basis of the system is the frequency, remember high school physics, there is a concussion, the development of technology, the larger, now is the semiconductor structure of crystal oscillator (I am not hardware, hardware name probably check). We used to calculate the 32 bit is not, the chip is processed, through a similar shift register of things, into a row of rows.

Serial port, meaning that the data is serial, we give a case-student queue, everyone through the serial port (doorway) out, now 32 people a row (shift register processing), now can be regarded as 32-bit parallel number. The meaning of the 32-bit calculation is that the byte width of the logical unit is calculated once, and now the data can be thrown out. Now we see parallel, you can think of the different or operation, through the basic XOR gate can form a specific switch (directive), this thank you for the Boolean NB (the Master of Mathematics-worship, not only the advanced graphic image needs mathematics, the computer Foundation is also a mathematical theory has its birth, As for the other multivariate equations, integral ... Although the high number did not learn how to figure out what is the use of learning it.

Just mentioned the frequency, why set the frequency?

--by the way, answer the second question of the question--this is a pseudo proposition, in principle the bit is not lost.

You do not tell the computer is 9600, it will not know the rate of data over there, it is assumed that you set the 9600*2, it at the rate of 9600*2 read what will happen? In fact, theoretically you can get the data, if the original is 2 bytes, then you will get 4 bytes is not? So the reason even digit and odd digits will be the same (timing accurate premise), to get the data you just need to take all the odd digits of the data can be obtained. Oh, well, what do you think? Is there a thing called octave?! Why is there a multiplier, why does the memory need to buy fixed frequency? is not a reason. (You can try a frequency, you can receive data, just ... ）

Light bulb is actually very easy, most of the interface has a control signal line one kind of things, raise it up, even on the light bulb and the bottom line is OK. The first problem we also solved, of course, with the data line in principle is also possible, hard to brush high-level data can (even if it internal consumption point what the naked eye can not see it, our use of alternating current 50hz).

Uh, talk about the code. Communication inside the personal sense of difficulty lies in the logical, in order to ensure the effectiveness of the data we tend to have a re-sending mechanism, a little careless is easy to fall into the trap of death cycle. This is indeed a need for clear logic. In the "game" article mentioned, because of a decryption reason at that time, our program egg pain. As for the TCP, which is called the Protocol family, that is not generally difficult, but the principle is the same principles, different places need to look at the needs, it to solve some of the problems (it is not really a lot of problems to solve).

Serial parallelism has a concept.

It's not a problem to come up with a single mouth.

--Since the call and the mouth, the data is not a write serial stream (software programming in the shield layer, encapsulated stream, of course, very advanced, Linux anyway is writing files, is also handsome). This thing we play with every mouth, like a row of rows of feeling. Oh oh, how to collect data over there, what next? It also has the control line not--the control line as the event notification: "There is data to come", "OK, I know, I immediately accept", "I finished."

--control motor swelling? Light bulbs are lit, high-power is not a problem, junior physics introduced the relay. Change the mouth to try how, can also pick up a number, this switch is very convenient.

"Game" We mention the security of the program files, the boss come up with a "mysterious" chip-"there is an agreement, forbidden to sell to North Korea or Iran." What is called security, only relative, from the hard drive to consider, do not run, there is no means to test memory, master everywhere Ah, crack flying, Windows is really more than Linux so unbearable? Why is there no cracked version of the domestic software? It doesn't depend on the user community, not on the technical issues. So we did not choose to encrypt the dog, dog fame, but more unsafe. This chip is hardware-level security, why our CPU can be low-end, high-side will not come out, not the theory of the ability to solve the problem, the manufacturing process is too weak. These chips crack-cut open the lid, microscopic, as long as the manufacturing technology can be OK, North Korea immediately can cottage. The "mystery" of the chip will not be, cut open self-destruction. Precision manufacturing is still painful for North Korea.

Silicon deposit, slicing, rigid--the hardware program (various instructions, of course, may also have registers) just so out.

The hardware program left the programming interface, this is our universal CPU, the lowest end of such as an adder, or use some of their own two-pipe combination (no parameters can be written, this is the non-programmable chip).

Hardware evolution, in order to improve security, there are multi-mode; Just like now the anti-theft door also upgraded, decorate a pattern, use a pattern. Switch to use mode, the permissions of the decoration mode has not changed.

Run the operating system, it also has to stay interface Ah, do not leave the interface how to run our program. Then a variety of virtual machines and provide a variety of exotic entry points-at that time to make a flash, get Flash Builder, did not find the entry point, asked a development for more than a year-unexpectedly, finally he finally found out, right-click Set Startup Items ... As for Android-unfriendly, personal or code-like main.

To be free to blow to this first.

From a communications chat computer