Chapter 111 Additional Circuit, Flying Line

Lin Hong saw the principle of the recorder clearly. Generally speaking, it is much simpler than the motherboard schematic diagram of the Apple's four-four computer. Lin Hong soon established the model of the recorder in his mind. He can even imagine how the data flows out of thin air.

I have to say that human wisdom is infinite. Lin Hong doesn't know who invented this design. Although this burner is simple, the principle is not much different from the reading and storage principle of the computer hard disk, and you can use a blank RPROM to pair a ready-made chip without relying on the computer. Copy the content.

"For this manual, you just need to look at the first half. The content involved in the second half is too complicated. Generally, it only has reference value for the designers and engineers of the recorder. We just need to use it, not at all."

Gu Wei saw that Lin Hongbi was looking at the second half of the manual, so he reminded him that the content of that part was too complicated for him.

He comes from a wild road. Although he can understand some common local circuits, when it comes to slightly more complex circuits with larger patterns, he is a little blind and can't understand them at all.

However, this is completely understandable, and this is a common problem for all amateurs. Anyway, they don't want to do scientific research. It's very good to be able to understand the local content, and it is usually enough to meet their own needs.

Just like this recorder, he doesn't need to fully understand its operating principle. He just needs to know what it can be used to accomplish. The games produced by the game company are still cracked.

Gu Wei didn't expect that in fact, Lin Hong had fully understood the circuit diagram.

This is based on his previous solid electrical foundation and the results of his study of the Red Book. Compared with what he saw before, this circuit diagram is relatively simple.

Gu Wei quickly gave all the data in the 2764 memory chip to DUMP.

He dragged the data into a small tool in a certain order.

"This is an encapsulation software. Just put these packets directly into it and then package them into a mirror file." Gu Wei explained to Lin Hong, "I don't even need to know which of these files is audio and which is an image file. This software can automatically identify them and place them where they should be."

Lin Hong nodded to show his understanding.

"This is the arcade game simulator. ... Gu Wei re-runs a software, and the content on the screen has changed, showing English.

Lin Hong saw the prompt "Please load the data file"

"The main reason why I switched to Z80 mode is to run this simulator, which can completely simulate the hardware environment of the arcade, so as to deceive the game program and make it think that it is running on the real arcade.

Gu Wei pressed the shortcut key on the keyboard a few times, found the previously encapsulated game file image package, put it in it, and then pressed the "re Enter key" to load. As a result, the display suddenly turned black and nothing could be seen.

"What? Is there an error in loading? Gu Wei was slightly stunned. Originally, he was very sure of something, but there was a problem.

He held down the shortcut key to exit the simulator program.

Then find a ready-made mirror package of other game files on the disk and run it in the simulator. As a result, the game screen "Gold Horse" soon appeared on the monitor.

"There is no problem with the simulator." Gu Wei said to himself, "Is it that the data file is incomplete?"

Then he checked the original game motherboard for a long time and finally found a new EPROM, model 27C320.

Seeing this IC memory, Gu Wei suddenly said, "I set it!"

Lin Hong: "What's the matter?"

"His uncle, there is also a memory here." Gu Wei said a rude word.

Lin Hong felt very strange. There is another one. Is it okay to continue DUMP?

"It seems that I'm unlucky today. I didn't expect that there was a 27C320 in this arcade. I guess the image data is stored in this." Gu Wei explained, "The capacity of this chip is relatively large, reaching 32 megabits. My burner can't read such a large EPROM at all."

After what he said, Lin Hong also remembered that the addressable space of his burner was up to eight megabits, which could not reach such a large capacity at all.

The full name of EPROM is "eraseable programmable read-only memory" is a storage chip whose data will not be lost after power failure. Its principle is similar to that of disk, but it is different. It is generally composed of a floating gate transistor, which can be programmed by an electronic device with a higher voltage than the common voltage in electronic . Once the programming is completed, the EPROM can only be erased by strong ultraviolet light. It is easy to identify EPROM through the transparent window that can see the silicon wafer at the top of the package, which is also used for ultraviolet erasure.

EPROM is divided into sizes, just like a drawer. Some drawers are large and contain a lot of things, while others are relatively small and can only hold a little.

2764 is a kind of "small drawer" with only 64K size. Because it is very cheap, it is used more and generally has a large number.

and 27

C320 is a large drawer, with a capacity of 32M bits, which is much larger than the capacity of 2764. Note EPROM is actually rare. In theory, when this game appeared, there was no such EPROM.

"Damn, it seems that this board itself is a modified board."

Gu Wei finally found something. He saw traces of re-welding around the chip, that is to say, the board had been modified.

What surprised him was that these traces seemed to have been carefully and specially handled. Ordinary people couldn't see them at all. If he hadn't had a preconceived consciousness in the first place, he would have looked for them with the intention of looking for traces, and he couldn't have seen them at all. That's why he didn't see it before.

Gu Wei felt very strange. It was really puzzling for this chip to appear on this board.

Lin Hong casually asked, "Where did you get this board?"

"One of my Dongbi villagers brought it here. He does all kinds of business. You know, he often goes to the Soviet Union to resell things. Many of my boards are from his hands. Lao Maozi's prices are very cheap now. He casually used some daily necessities and exchanged a lot of such things. In fact, these things, to put it bluntly, are some foreign garbage, which are imported from abroad by Lao Maozi. This board is some years old...,..."

Lin Hong nodded slightly: "That is to say, this board may have been changed by the old man?" Yes." Gu Wei was a little helpless. "I can't read such a large memory chip with my recorder at all. It's a pity. I don't know what good things are in it. I'm willing to use a 27C320. As far as I know, "Sharoman Snake" can't use such a chip. Lao Maozi's skill is also very awesome. There must be something special in it. Gu Wei was very sorry. At this moment, he really wanted to DUMP the data in this chip, but there was no corresponding equipment. It was really difficult for a skillful woman to cook without rice, and he was very depressed.

"As far as I know, it is difficult to find a burner that supports a larger volume in the whole Zhongguancun market in a short period of time. It is estimated that it will take a temporary purchase from Guangzhou. I have no choice but to look back." Gu Wei intends to give up.

"Maybe I have a way to get the data DUMP out of it." Lin Hong suddenly said after a long silence.

"Do you have a way?" Gu Wei immediately opened his eyes and looked at him, "What can you do?" Although he didn't think so, he asked out of politeness.

Knowing that there was no large-capacity recorder, a rookie who had just come into contact with this industry actually said that he had a way to give the data in the 27C320 to DUMP, which not only made him feel a little funny. He had been in the industry for so many years, and there was nothing he could do, let alone him. Gu Wei believes that even his master can't do anything about it here.

"I just looked at the circuit diagram of this recorder. I think that because it pursues too much stability, it sacrifices a lot of efficiency, thus limiting his addressing space. Many of the circuits in it are actually redundant, which can be streamlined in a clever way." Lin Hong took out the user manual of the recorder, opened the page of the circuit diagram, and then said, "Actually, you can add an additional circuit here, and then fly a wire from here and here, so that the remaining large piece of circuit can be completely streamlined. Through this additional circuit, the addressing space of the burner can be quadrupled, that is, 3 megabits. With that, Lin Hong drew a line on the schematic diagram of the recorder with his nails.

Gu Wei looked at Lin Hong in surprise, and his eyes seemed to see an alien.

"Don't tell me that you have fully understood this schematic?"

"I probably understand it." Shit!"

"Damn it!" Shit!!"

Gu Weilian "rely" three times to express his mood at this moment.

What Lin Hong said seemed to have a basis, and he believed half of it. Although he wanted to believe it all, the fact was too exaggerated for him to accept at all.

Gu Wei quickly found a pen and paper and asked Lin Hong to draw out the additional circuit he said.

Lin Hong is not polite. He picked up the pen and brushed it on white paper a few times to draw a fairly simple circuit.

From the level of drawing the circuit, Gu Wei knew that Lin Hong was an agruent. Not only did the representative symbols of various electronic components fully meet the national standards, but the lines drawn casually were simply more straight than those he drew with a ruler.

"Professional, he is so professional!"

When Gu Wei saw his circuit diagram, he actually felt filthy, just like the pirated version met the genuine version.

"This circuit is to add two additional bits to the burner, which can represent 0,1,

2, 3 and four states, which is equivalent to four 8 megabytes of space available to use the flying line are connected to these two points. Of course, the flying line can be used or not, but using the flying line can speed up the speed of DUMP. According to my calculation, the speed should be increased by about two times.