Bit Mania [Hacking]

Quhai University.

Lin Guang and Li Yunze carried the repaired Macintosh and appeared outside the computer laboratory. They looked around and saw no one, so they quickly took out the key to open the laboratory, moved the computer to its original location, and plugged it in. Good power, can't wait to press the power button.

The two rubbed their hands anxiously and excitedly, and leaned together in front of the computer. The normal boot screen appeared on the screen. Li Yunze operated the mouse to check the computer environment, and made an OK gesture to Lin Guang.

"It's finally fixed. It's a false alarm. Let's continue with the project." Lin Guang let out a long breath.

"Okay." Li Yunze responded, and clicked on the database software they had written halfway through.

At this time, the professors of the computer department of the college also walked into the laboratory, seeming to be discussing something intensely, and vaguely heard words such as "source code".

"According to the situation described by the students at that time, although the expert played a leading role in the decryption process, the mathematics support of our school also contributed a lot..."

"And the old man still left the source code in our school, and no one has seen such an important thing come to take it. Perhaps the intention of that expert is self-evident..."

"I think so. With the strength of our entire computer department, I think the next thing to do is still competent. We can't let that person down..."

The professors were chatting, and when they turned around and saw the two of them fiddling with their graduation projects in front of the computer, they nodded in relief.

"Ah!" Li Yunze suddenly let out a scream, and Lin Guang quickly covered his mouth.

"What happened?" A professor seemed to be in a good mood. Hearing the sound, he came to this side: "Is there any difficulty?"

"No, no, no..." The two of them shook their heads desperately with pale faces.

"It just so happens that I'm free now, let me see how your progress is going."

"No no, teach, professor, we haven't finished yet, don't bother you..." Baldy Lin shook his head like a rattle, and he secretly glanced at the half-programmed software. For some reason, dozens of these codes were missing. It has become full of holes. If such a thing is seen by the professor, a scolding will definitely be inevitable.

"That's right!" Li Yunze also agreed with a pale face.

"There's nothing to be embarrassed about. I'll check for you now. If there are any fundamental mistakes, I'll find out as soon as possible." The professor walked up to the two of them and looked at the code on the computer.

Seeing that Lin and Li couldn't stop them, they could only stand beside them tremblingly with bitter faces.

The expression on the professor's face sank at a speed visible to the naked eye, and he became extremely dignified. Suddenly he raised his head and shouted in the direction of the other professors: "Come over here, you guys, take a look at this!"

Several professors approached curiously, and the scene gradually quieted down.

"This...multiple processes or threads can access the same data at the same time without any problem?" A professor's eyes widened.

"That is to say, the same database can be read in parallel at the same time..."

"Professor Xue, what do you think?"

"No, although it can be read, only one process or thread can write data at a time, otherwise it will fail to write and get an error message!"

"But I think it's an innovation that makes databases more useful, especially when used with untyped scripting languages..."

Someone else retorted: "But I think this is a serious shortcoming of irresponsibility!"

"professor Zhang……"

"The program may automatically retry for a period of time, and the length of the retry time can be set..."

"So even so, I think it's still doable!"

"It's not rigorous at all!"

"I didn't call you here to fight with you!"

"Me too! But..."

"Hey!..."

Seeing the expressions of the professors getting more and more excited, all of them were blushing and nearly raised their arms to perform martial arts, two pale-faced college students tried to speak: "I, we..."

"Shut up!" a professor yelled back, and turned to continue arguing fiercely with his colleagues.

"Our graduation project..." The two wanted to cry but had no tears.

"Does it even need to be said!"

Is it true that God is going to kill me?The two looked at each other, and they both saw despair on each other's faces. They took a last look at the professors who were quarreling together, and helped each other out of the laboratory with helplessness, and went out to the professor who had always been respected. They closed the door, which also prevented the two from hearing a professor's sigh after they closed the door: "But there is no doubt that this is a milestone masterpiece..."

-

After Luo Zixin made a rough parts list in the library, it was already dark. He looked up at the clock and decided to go to the recycling station for old electrical appliances before going home.

Going this time, obviously with a clear purpose.Since Zixin has made up his mind to build a "subcomputer", the first difficulty that needs to be overcome is the core of the entire computer - the central processing unit CPU.This is the heart of the whole machine, without it, all other ideas are just a bubble.

For this reason, his first thought was to replace it with a single-chip microcomputer.Single-chip microcomputer, also known as single-chip microcomputer, is a microcomputer that integrates the central processing unit, memory, timer/counter, and various input and output interfaces on an integrated circuit chip. All of them are embedded operating systems, which are extremely simple and effective.

Compared with general-purpose microprocessors used in personal computers, single-chip microcomputers emphasize self-supply. To put it bluntly, they are small in size, simple in operation, low in storage capacity, single in function, and low in cost.

What makes Luo Zixin very optimistic is that it is generally easy to make a working computer with a single-chip microcomputer with an external support chip, so that the single-chip microcomputer system can be implanted inside the device to control the device. What is more interesting is that the single-chip microcomputer not only has input and output devices, but also There are other serial communication interfaces, that is to say, through special instructions, external equipment and certain modifications, Luo Zixin can even make it into a computer that can connect to the Internet!

So, here comes the question, where does this MCU come from?The answer is surprising - household appliances.However, not all home appliances are equipped with such a simple version of the microcomputer, they must be fully automatic washing machines, microwave ovens, air conditioners, refrigerators and other high-end products.

In the small town in the early 90s, there were really not many families capable of using these electrical appliances, so Luo Zixin’s plan was to greet the staff at the recycling station as soon as possible, and let them take care of him. Zixin was ready to wait for a while. As long as any such electrical appliances are sent to the recycling bin, he will be notified as soon as possible. As for whether the single-chip microcomputer inside is damaged or not--Luo Zixin believes that as long as it is not too broken, he who knows it well will still able to fix it.

Without further ado, making up his mind, he closed his book and headed to the old electronics recycling station southwest of town.

He is in the field of electrical maintenance, so naturally he often deals with the staff of the recycling station. The old men there also like this well-behaved and polite boy. Luo Zixin can often find a lot of useful things at a relatively low price there. thing.

Three off-white trucks were parked at the door of the recycling station, loading and unloading old electrical appliances. Luo Zixin walked up to them familiarly, and one of the workers who was carrying them recognized him and greeted: "Xiao Luo, Why are you here so late? What do you want this time?"

Luo Zixin yelled "Uncle Liu", walked forward quickly, and helped the worker move a TV into the recycling bin together, and then explained to the other party why he came.

"...Electrical appliances with a single-chip microcomputer?" The worker known as Uncle Liu touched his chin: "We haven't received it recently... You know, there are only a few households in the whole town now, otherwise it is the government and the government. Most of the business units were purchased in the past two years, and it is difficult to come across scrapped machines.”

After all, he was still young, and the expression on the boy's face clearly showed how disappointed he was: "That's it... If you receive it, please notify me as soon as possible, and I am willing to pay one hundred yuan."

He was about to turn around and leave, but Uncle Liu stopped him: "By the way, Xiao Luo, wait a minute." The worker scratched the back of his head: "I have something here, I don't know what it is useful for, Xiao Luo, you know a lot, help me." Let me see what this is?"

Luo Zixin said hello, and followed the workers into the warehouse behind the recycling bin.

There was a faint smell of dust in the warehouse. Liu Bobo turned on the light, and the scene inside could be seen at a glance. The man walked up, rummaged through a pile of electrical appliances, and finally took out a piece of dusty one. The plate was about one foot long and half a foot wide. When Luo Zixin took it, his hands were immediately covered with dust.

He stared blankly at the board in his hand, and carefully brushed off the dust on it, revealing the original white body of the board and the black keyboard inlaid in it, and a string of big red letters on it—LASER310.

"How is it? Do you recognize it?" Uncle Liu approached and asked.

Zixin woke up startled, and let out a long breath: "This, this is a microcomputer!... Where did you get it?"

"Microcomputer?" Uncle Liu said with a confused look on his face, "Oh, this was given to me by a nearby high school... What is it, can it cook?"

"...except for cooking, I can do anything." Luo Zixin swallowed a mouthful of saliva: "Uncle Liu, do you use this machine? Can you make a price and sell it to me?"

"Ah, I don't know what this is. It's useless to put it here. How about it? If you want it, I'll give you 20 yuan!"

"...a lot, a lot, how much?"

"20 yuan, is it too much, then fifteen."

……

Luo Zixin was still absent-minded until he walked out of the back door of the recycle bin.Others may not know what the square machine board in his hand is, but the boy clearly understands the value behind it——

The first generation of personal computers introduced by Huaguo!

Originally, I just wanted to buy an egg, but found an old hen instead. Although LASER can only be regarded as a "claw machine" compared to the American Apple machine whose structure has become mature, but this microcomputer imported from Taiwan, compared with the greatly simplified integrated chip of the single-chip microcomputer, is actually Already well it's not 01:30.

A certain person was so happy that when he walked out of the recycling bin, he didn't pay attention to the movement on the side of the road, and happened to bump into the muzzle of a mad dog, so when he was holding the LASER and was out of breath, he was chased by the animal , finally deeply understood the meaning of the phrase "extreme joy begets sorrow", and was chased straight for half a street without distinguishing between indiscriminate and indiscriminate.

This made sports waste a lot of trouble. He ran into a construction site with his hands and feet holding the computer, and climbed onto the thick steel pipes piled up together. Jump up on your legs.

He resisted the urge to be rough, and climbed up with rage. The big dog behind him stepped on the steel pipe, and his heavy weight rolled the triangular pipes. Luo Zixin slipped, and suddenly a sharp pain spread from his ankle Come.

It's twisted!Seeing that the big dog was about to pounce on him, Zixin turned forward with all his strength, rolled down from the other side of the pile of steel pipes, and fell heavily to the ground.

His whole body hurts like falling apart, the shiny old thing stepped on the highest point of the pile of steel pipes with its front paws, grinning and looking down, its muscular hind legs gradually bent, and it was about to jump down.

All the poor boy could do now was to curl up in a ball in terror and shout, "Help!"

"Wow!——" Just as he was so frightened that he couldn't help closing his eyes, the big dog suddenly let out a scream and fell off the pile of steel pipes.

Zixin opened his eyes in surprise and looked up. On the high pile of steel pipes, a foot wearing casual shoes stepped on the top, and a figure was standing there looking down with an unknown object in his hand. Myself, the background is a furry moon.