Chapter 290 Single Board Computer Hardware
The two of them joked for a while before Yu Yuncheng got down to business: "Director Gao, are they still going to do this appraisal? I'm thinking about another project of yours. It's not a good idea to keep wasting our time like this, haha."

Gao Zhendong also thought of this matter: "Well, I'll ask later. Anyway, you are ready. You can take a rest these few days. I think you are very tired during this period. Why not just bring your wife to Beijing to reunite. We can talk about the new project after Labor Day."

Gao Zhendong did not say to give Yu Yuncheng a holiday directly to let him return to Haihekou 1761 Institute to reunite with his family. When the final results are about to be released, regardless of whether it is out of good intentions or not, the fact is that sending people away from the front line can easily cause misunderstandings.

If Yu Yuncheng himself wanted to return to Haihekou, he would have brought it up himself. In short, this matter could not be brought up by Gao Zhendong.

The next project, cadmium mercury telluride, is not so urgent. Just as time passes by, one cannot eat hot tofu in a hurry.

Yu Yuncheng smiled and said, "Okay, I'll just be lazy. But when it comes to being tired, I'm much better than you. You still have to take care of your health."

He naturally noticed how busy Gao Zhendong was and gave him a reminder.

Gao Zhendong left the newspaper to Yu Yuncheng as a souvenir. As for himself, he just needed to find another copy. In this regard, Yu Yuncheng was not as convenient as him.

At this time, the factory radio was already broadcasting two reports from the Daily News, which were broadcast in rotation eight times a day.

Gao Zhendong didn't care about the commotion in the factory. He now had something exciting to do.

——The hardware of the single-board computer has basically been debugged.

Today's single-board computers are not as neat and exquisite as when they were first made and delivered to us by the computing institute.

The entire board was covered with flying wires of various colors, and the copper foil on the board had signs of being scratched everywhere.

The flying wires are either soldered to the pads or to the scraped copper foil, and the melted and re-solidified dark brown rosin can be seen everywhere on the circuit board.

What's worse, there are a small number of flying wires that are difficult to find a place to solder, so they are directly soldered to the pins of the chip or discrete components.

This is probably the ugliest board produced by Gao Zhendong, but in Gao Zhendong's opinion, this thing is more significant than DJS-59, because DJS-59 is difficult to popularize, but this thing can.

The entire board is divided into four equal areas, and the four areas are separated by a row of holes similar to stamp holes.

The four areas are not squares, but the four corners are missing a part of basically the same size and no lines are arranged.

What is most puzzling is that there are no connecting lines between the four boards except for the stamp hole separations. The four boards are connected by several wiring cables that directly cross the stamp hole separation lines.

However, although it was ugly, Gao Zhendong was obviously very satisfied with his work. He walked out of the computer room, washed his hands, dried them, and then came back.

His series of actions had nothing to do with burning incense and bathing, they were just to prevent static electricity. Especially the thin woolen clothes he was wearing, which were a big source of static electricity. When he took off his clothes, he could hear the snapping sound, and even saw flashes in the dark.

Gao Zhendong put on the anti-static wristband and started to connect the peripheral cables. The anti-static wristband is not a high-tech thing, but it is quite useful.

A characteristic of safety facilities and equipment is that when they are in use, you don't realize that they are useful. When you realize that you should use them, it is often too late.

Gao Zhendong was not in a hurry. He had suffered from being clumsy before. In his previous life, when he was installing a computer, he dropped an iron lighter directly onto the motherboard, and the motherboard broke down on the spot.

He connected XS-59, JP-59, modems, tape drives, magnetic core memories, and even the DY-60 which had just arrived.

Each item has been connected and basically tested before, but this is the first time that all of them have been connected.

Just because it's okay to connect them separately doesn't mean it's okay to connect them all. Gao Zhendong is just waiting for this last moment.

It's not like he hadn't had a power supply explode in his previous life, so he has a lot of experience.

With some caution, Gao Zhendong turned off the main power of the single-board computer and peripherals. "Don't let it explode, don't let it explode," he muttered to himself.

The single board computer was very considerate and there was no crackling sound. But you have to know that when the resistors, capacitors and chips explode, they really explode.

There is no output on the monitor, but this is normal. The BIOS of the single-board computer is still in the magnetic core of DJS-59. It will not be transplanted until the power-on test is OK.

Gao Zhendong stretched his nose and passed it all the way over the circuit board of the single-board computer. While moving his nose slowly, he kept inhaling through his nose.

This is one of the most primitive detection methods. Just smell it to see if it is paste or not. It is quite effective.

If there is a burnt smell, turn off the power immediately. The circuit board is based on bakelite (phenolic resin). If it is burnt, the smell is quite special and you can smell it immediately. The same is true for other components that are burnt.

There is no way. The lines are dense and there are flying wires blocking the view. At this time, it is better to smell it than to see with your eyes.

At the same time, his eyes were fixed on the output voltage and output current display tubes of the power supply. Through these data, he could roughly judge whether the startup of these devices was basically normal. If the current could not run up, there was a problem, there was no power supply or the power supply was incomplete. If the current ran too high, there was a short circuit. If the current fluctuated up and down and its fluctuations were not in line with expectations, it was possible that the startup process was stuck or entered a loop. The most annoying one was the last one, which was too difficult to check.

The same goes for voltage; if it plummets, it means big trouble.

Gao Zhendong, who temporarily transformed himself into a dog, sniffed for a while and did not smell any special burnt smell. The current was also normal and the changes were in line with expectations.

Gao Zhendong clapped his fists and palms together: "Haha, it's done."

Combined with his previous debugging process and results, this means that there are no problems with the single-board computer's hardware and external interfaces.

There is even unexpected good news: the operating frequency of the single-board computer is 59% higher than that of DJS-20!

The reason is not surprising. Integrated circuits bring better device consistency, fewer peripheral components, simpler circuits, and improved reliability brought about by advances in manufacturing processes. These make single-board computers more reliable than DJS-59.

Next, there is the issue of software.

Speaking of software, the first thing that comes to mind is of course BIOS. Without it, it would be difficult to implement other software.

Fortunately, I already have a DJS-59, so writing BIOS is much more convenient than when I worked on the DJS-59 before. I can write and debug directly on the DJS-59, and then write the compiled results into the single-board computer memory.

Another advantage of single-board computers is that their basic architecture is actually the same as that of the DJS-59. The biggest difference lies in the number of registers and addressing range. As for the ALU, instruction decoding, data bit width, peripheral interface, instruction set, etc., both are the same.

Therefore, the DJS-59 BIOS only needs to be modified to be used directly on the single-board computer, which is not a lot of work.

Gao Zhendong has completed the modification work, and now he needs to verify it.

Gao Zhendong turned off the single-board computer, connected the magnetic core memory to the DJS-59, then turned on the DJS-59 and began writing the single-board computer BIOS.

It seems a bit troublesome, but hot-plugging is not supported these days. If you insist on doing it, it is easy to change from hot-plugging (IT) to hot-plugging (physical).

After a series of somewhat tedious operations, Gao Zhendong reconnected the magnetic core memory to the single-board computer and started the single-board computer.

A "beep" sound was heard, and Gao Zhendong felt relieved.

At least the system has entered self-check.

Gao Zhendong stared at the screen. As he waited anxiously, there were a few more "beep beep beep" sounds, and a line of words popped up on the XS-59.

"DJS-60D, BIOS Jiu Xu"

A cursor was jumping below the line of text.

"Done!" Gao Zhendong was so excited that he even said his catchphrase from his previous life.

He has given the single-board computer a name, DJS, inherited from DJS-59, which is unshakable, 60, meaning 1960, and as for the D, it represents the "single" in "single-board computer".

This method can be regarded as the stamp of Gao Zhendong's military fandom in his previous life. QBZ and QSZ came from this.

"JiuXu" is simple, "just ready". This thing is different from C language and other languages ​​that we hope to promote both at home and abroad. For domestic use, Chinese pinyin will do. If it were possible to organize the Chinese character library in BIOS, Gao Zhendong would have changed it to "just ready".

Gao Zhendong turned off the single-board computer and returned to the DJS-59. Next, he would transplant the loop-duty environment of the DJS-59 to the single-board computer.

This work is tedious, but not difficult.

Most of the work is to modify the header file of the C language project of the DJS-59 loop duty environment, change the predefined register quantity, name, addressing width and other parameters to be consistent with the single-board computer, and at the same time change some excessive things in the program.

Gao Zhendong only planned to change the loop duty environment, and at most add a small program to test the computer's computing power by calculating pi. He would not change anything else.

As for how to solve other supporting programs, that’s easy. Just call people and give them a shout, and the comrades from the Computing Institute will rush up shouting.

The workload is not very large, and it will probably be completed after May Day. It’s just a Labor Day gift, so I might as well make one.

Even if it can't be completed in time for May Day, it can be made into a Children's Day gift, right? At worst, we can transplant Snake or Tetris on it as a holiday gift for children. Perfect, the plan works!
Regarding this matter, a later article studying the history of domestic electronic games, "A History of Domestic Games", wrote the following.

"The first domestic electronic game was "Snake", a self-entertainment game created by Mr. Gao Zhendong, the founder of my country's information technology, in 1959. The game was once popular among my country's first generation of information technology personnel. But the first domestic electronic game seen by the public was "Stacking Bricks", which Mr. Gao Zhendong specially compiled on the first domestic personal computer in 1960 to celebrate the festival for children. It later had a more familiar name around the world - "Huaxia Stone."

(End of this chapter)