How to update a laptop using a 3-D printer
Hello, my name is Dmitry. As you know, only desktops can be upgraded. Laptops, when they become obsolete, are simply thrown into the trash. But today I will tell you about my experience in upgrading a laptop. And for this I only needed a 3-D printer.
You know, many people criticize Intel for releasing a new socket every two years, arguing that the power consumption of new processors has increased so significantly that the old socket is simply unable to transfer sufficient power to the new processor. But some people see this as planned obsolescence for motherboards, so that people would buy new motherboards more often, and not sit on the same one year after year.
Well, the situation with laptops is even more terrible. If your laptop is outdated, then you cannot change the processor and motherboard; you need to throw out the old laptop and buy a new one. And this is terrible, because for example, I still have an old laptop in which the matrix and keyboard and SSD work, and it turns out that I have to throw it all into a landfill. But thanks to the fact that we have a 3-D printer, we can break this terrible vicious circle. So let's get started.
Motherboard.
I purchased on Aliexpress motherboard for mini pc. You could argue that it's just a mini-ITX board. But if you look closely, you can see that it does not have a standard 24-pin power connector, it simply connects to 12 volts. You can also notice that it uses sodimm strips, which are used in laptops and mini PCs. The processor used here is Intel Celeron N5095. Of course, we can say that the update is so-so. But my Acer Aspire 1425p had a Celeron SU2300 (1.2 GHz, 2 cores).
Monitor
This is where the fun begins. If you have an old laptop, then you can remove the matrix from it. But it won’t work just like that, since it connects to the LVDS (low-voltage differential signaling) interface, and we need hdmi or, at worst, dvi. But Aliexpress also sells so-called scaler boards. Scalers can be either universal, in which the resolution is selected by jumpers, or scalers designed for a specific type of matrix. For example, I just looked at what matrix is in my laptop (Samsung LTN116AT01-A01) and looked for a scaler using this designation. You also need to pay attention to the fact that not all scalers support audio output. It’s better, of course, to buy one with sound, otherwise you’ll have to wire the amplifier yourself and somehow feed it a signal from the computer.
Keyboard
We also take the keyboard from the laptop. But the problem is that the keyboard controller is located on the laptop board. That is, you will need a controller for the keyboard.
I will use the stm32 Blue Pill board as the controller. The main advantage of this board is that it has a USB port. Moreover, this is not some fictitious port (which is actually a Uart) like the Arduino, but a real, full-speed one operating at 48 megahertz.
If you don’t know how the keyboard is controlled, then google “matrix keyboard”.
I did the firmware using here's this lesson I will not repeat here what is written there, the only thing I will say is that when you flash your Blue Pill, be sure to put the jumpers in position 0, otherwise during flashing you will have errors and you will not understand what is happening.
In the repository at the end of the article you will find my sources, I compiled this project in Platformio and I created the project template in the Stm32CubeMX program. When you create a project, CubeMX will complain about missing libraries, but this is normal because Platformio will pull up all the libraries, so you can simply ignore these errors.
If you just want to compile my project in Platformio, you won’t succeed because by default in the usbd_hid.c file our device is designated as a mouse and we need a keyboard. So you'll still have to switch to this lesson and see how to replace the device with a keyboard. Links to the Stm32CubeMX StLink driver files as well as a file with a description of the keyboard will be attached at the end of the article. Also in the repository is an electrical diagram made in the Proteus program.
Sound
But I won’t take the speakers from the old laptop. Firstly, they have absolutely no low frequencies. That is, when listening to music, you will hear the cello but will not hear the double bass at all. In addition, the sound they create is quite quiet. I’ve often had a situation where you’re watching a movie, explosions and gunshots are audible well, but speech is unintelligible, and you want to turn it up, but you can’t make it louder at the maximum volume. So I bought AIYIMA speakers.
But I wanted it to be not just some kind of sound, but it was designed as two small speakers. The fact is that when the speaker membrane creates sound, its reverse side also creates sound but in antiphase, as a result, these two sounds cancel each other out. Of course, this process is not ideal, so you will hear some sound, but this sound will be much quieter than it could be. And in order to block this “harmful” sound, the speakers are made hermetically sealed, and materials that absorb sound are also placed there, well, all kinds of foam rubber, cotton wool, etc.
Actually, I did just that, but I didn’t mess with the cotton wool and put the packaging material in which the motherboard was packed.
Frame
I printed the body on a 3D printer. (Here is an article about my 3D printer if you haven't read it, I highly recommend it). Its design may seem strange in some ways, but you need to consider that my 3D printer can print parts no larger than 230x150mm, so I had to divide some parts into two parts, and some into three.
At the end of the article there will be a link to a repository with a 3-d model, it was made in the Creo parametric program (formerly ProEngineer). There is also a PDF file with a 3-D model in the repository, but GitHub cannot view 3-D content, so to view it you need to download the file and view it through Acrobat reader.
Design overview.
Well, a small photo gallery:
When assembled, my laptop is a rectangular parallelepiped measuring 280x245x65mm, which can be easily and comfortably carried in a medium-sized bag.
Inside the main part there is an SSD and a keyboard controller.
Inside the part with the monitor there is a 12V 6A power supply and a scaler. Since I don't intend to use it on the road, I don't need a battery. I just need a compact computer that I can take to the dacha and use there.
You can see that wires are soldered to the scaler. The fact is that the scaller pads have a pitch of 2mm. And since I don't have such connectors, I just had to solder wires instead of connectors.
Conclusion
Well, now you know that you don’t need to throw away your old laptop, it can be easily and simply modified and it will serve you for many years. In the next article we will modify a smartphone.
