Super Copy of Great Power Technology

Chapter 77 Tape-out Results
As early as after the preliminary chip design was completed, Zhou Ruida purchased electronic components such as LCD screens, micro-key switches, NAND Flash memory chips, resistors, capacitors, etc. used in making MP3 players.I have ordered printed circuit boards for testing chips. Compared with the scarcity of wafer foundries, there are not many factories that can process printed circuit boards for me.In order to grab business, some factories even provide free board printing services.

After arriving at Reda Technology Company, Qiao Reda immediately returned to his office.Open the drawer and take out a lot of electronic components, circuit boards, flux, a constant temperature soldering iron, and a heat gun.Start soldering the components according to the circuit diagram.As a novice, Qiao Ruida's movements were very clumsy. The soldered circuit board was numb and ugly, with large and small solder joints, odd shapes, and not very round and beautiful.The flash memory chip and the main control decoding chip were the most difficult to solder. It took several back and forth attempts before we successfully soldered them.

An hour later, an extremely ugly naked MP3 player was assembled.Qiao Ruida found a mobile phone data cable, connected the player to the computer, and burned the pre-compiled hardware program into the main control chip.A few minutes later, the program programming was completed, the player automatically restarted, and the 0.96-inch LCD screen on the front lit up for the first time.The logo of Reda Technology flashed by, a somewhat crude interface appeared on the screen, and an icon of a removable hard drive popped up on the computer.

Seeing that the interface set by the code actually appeared on the LCD screen of the player, Qiao Ruida was immediately overjoyed and couldn't help waving her arms and yelling, "Yeah, it worked!"

Qiao Ruida's voice was so loud that it spread through the door and was heard by more than a dozen employees working near the general manager's office.

"Hey, this voice is coming from the boss's office. What happened to make our boss so happy?"

"Perhaps I was looking at this month's financial statements to celebrate the great success of Reda Mall."

"Our boss is so young, maybe he has finished playing games."

"I guess the boss has achieved something academically, and academics are what our boss values ​​most."

The employees' speculations were far from the truth, and Qiao Ruida paid flawless attention.

At this time, Qiao Ruida had already broken free from her excitement and continued with the next test.He operated the mouse to format the removable hard drive, and then copied some audio files in mp3, aac, wave, ape, Flac and other formats to the removable hard drive for subsequent testing.

After unplugging the data cable, Qiao Ruida pressed the play button on the player. The next moment, the number one song "Gong Xi Fa Cai" entered the playback state, and the album cover and lyrics were displayed on the LCD screen.Since there are no speakers welded to the player, no sound comes out. If you want to continue testing, you can only find a pair of headphones and plug them in.

Qiao Ruida opened the drawer and rummaged through it, but couldn't find the headphones.As a reborn person, Qiao Ruida has long been accustomed to various Bluetooth wireless headphones in her previous life. She is really not interested in the current wired headphones, so she has never used them.In desperation, Qiao Ruida had no choice but to walk out of the office, went to the public office area, and borrowed a pair of headphones from an employee.Nowadays, mobile phones generally have 3.5mm headphone jacks. Most people who like to listen to music on their mobile phones have headphones.

After returning to the general manager's office, Qiao Ruida put the headphones on her ears, and then plugged the plug into the MP3 player. A burst of high-pitched music suddenly sounded in her ears, "Just to watch the bright white moonlight with you, swim through the four seasons." The lotus is still fragrant, waiting for you in the middle of the water, and the fireflies light up the stars of the night..." The singing voice is clear, loud, rich in details, and has a first-class listening experience, no less than those popular MP3 players currently on the market.After pressing the pause button, the player immediately enters a mute state, and the background noise is almost inaudible.Press the key to switch to the next song, which is a lossless music in Flac format. The file is much larger and the sound quality is better.Playback is still smooth without any lag.Qiao Ruida is not a music enthusiast. She can't tell the size of the sound field or the positioning of the instruments. She only knows that this song is more listenable and ear-catching, and the listening experience is much better than those over-compressed MP3 songs.Next, he tested playing various song files in different formats and different compression ratios, and all of them could be played smoothly.Pause, fast forward, timely response, no mistakes or omissions.

After playing them all, Qiao Ruida downloaded some treble songs, bass songs, pure music, piano music and other types of music files from the Internet, copied them into the player and tested them. Everything played normally.

When Qiao Ruida connected to the computer for the third time and copied files to the player, an accident occurred. The computer prompted a message that the target disk was full and the copy failed.

"How is this possible? I remember that the circuit board was soldered to a 4G-sized flash memory chip. It only contained more than 20 music files. Why is it full!"

With doubts, Qiao Ruida checked the circuit board again. It was indeed SanDisk's 4G flash memory chip soldered on it.Then I looked at the mobile drive letter on the computer and finally found something wrong. The size of the hard disk displayed at this time was only 156M. No wonder it could only store about 20 files.

When you find a problem, try to solve it.Qiao Ruida first found the source code of the hardware program and went through it from beginning to end, but found no problems.I took out the soldered player and checked all the electronic components and solder joints, but found nothing wrong.In order to further troubleshoot, Qiao Ruida welded a second MP3 player, this time choosing a Panasonic 8G flash memory chip as storage.

With the previous welding experience, the second MP3 player only took half an hour to weld.After connecting to the computer and burning in the hardware program, I formatted the mobile hard drive and saw that the size was only 312M.

"The faults are similar. The storage space has shrunk severely. The flash memory chips used twice are not of the same capacity or brand. This should be able to rule out compatibility issues with the flash memory chips. The rest can only be solved from the circuit board or the mainframe. Find the problem on the control chip.”

Qiao Ruida opened the EDA software and rechecked the circuit board wiring diagram. Everything was normal.In this way, the conclusion is very clear, that is, there is a problem with the audio decoding chip he designed, and the tapeout failed this time.

"Huh, let me just say, things can never be smooth sailing. Some setbacks are normal. Next, let me see what went wrong."

(End of this chapter)