Keyboard-With-Utility
A mechanical keyboard that has a screen and you can plug a mouse into
May 23: It begins. Some planning and schematic work.
After thinking for a little while, I settled on a mechanical keyboard with an LCD and some USB ports. This will be my first time designing a PCB, and I don't want to choose something to diffifult, but I think this should be doable and pretty cool. To start, I looked online for similar designs, and found some things I can potentially use as reference. (Pi Pico Keyboard, PCB Keyboard, and USB hub). I decided to use KiCad to design the PCB because it seems pretty widely used is free.
I am going to use a Rapsberry Pi Pico because of its small form factor, low price, and popular use in similar projects. It looks like if I want to be able to split the USB input, I will need to have the Pi Pico connected downstream of something else, so I won't be able to use the USB connector it comes with. Based on the datasheet, though, I should be able to surface mount it onto the PCB and use the test points to make a connector. Looking online, it seems like I can apply solder paste to the PCB, place the Pico on, and heat it up with a hot air soldering gun. Unfortunately, these cost around $30 so I may have to find some workaround. It seems kind of janky, but it might be better to just use a cable that plugs into the pico but is attatched internally. If I can't get this to work, I may have to abandon the extra ports :(
After spending a little while trying to input pcb elements into kicad, I decided to just use EasyEda, because it is also free, seems easier, and many of the LCSC components easily available. Unfortunately, I am having some problems understanding the pinout of the USB-C connector which I want the keyboard to connect with. I have to go to bed now, but this is what I have so far.
Today, work has been somewhat slow, but I think it should start to go better once I have this software figured out.
4 hrs
May 24: Schematics
Today I want to mostly finish the schematics, at least for the keyboard part. Last time, I forgot to save my schematic, but it is fine, because I only made slight progresss. Since I want to use USB-C, I needed to figure out what the special pins are for. It seems like many of them can be shorted, but CC1 and CC2 need to be pulled down. Next, I looked on the components catalog and found what I was looking for earlier: 4 pin wire to board connector. This should let me plug the Pico in without needing the test points. I made a test PCB to see about specific parts, and everything is fine except for the Pico, which it can only make the pads for (assembly costs +$50), so I will solder it on manually. I also added the USB-A ports for mice and etc.. It is taking a while to find the correct components and figure out how to read the spec sheets, but I think I am getting a hang of it. This is what I have so far.
Thinking more about the display on the keyboard, I think that I will make it be a Now Playing
thing like this Spotify display
2.5 hrs
# May 25: Key layout
Now, it is time to make the keyboard. I used keyboard-layout-editor.com to generate a layout that I like. After doing some reasearch I think that I am going to use a slightly modified 75% keyboard with space for the screen that I want to add. I think I will use these keycaps because they look cool and are pretty cheap. They also support many keyboard layouts.
0.5 hours
June 22/23: The screen
After a long break for no reason, I am back to this project. I realized that the deadline is coming up, so I have to finish this.
Most of this project has been (sort of) simple up until this part for me. I want to be able to read my plugged in computers now playing
window. Using this, I am, hopefully, going to display song title, artist, progress, and album cover. I think the easiest way to do this will be sung the winsdk python library. I used AI (I know I know, but I'll re-write it myself later) to generate some code that downloads the media thumbnail, shows the artist, progress, and song title. This worked (after some modification), and I think this proves that it will be possible to send the data serially to the display. I'm probably going to send the image and text to whatever microcontroller I use, and process it with this TFT display repository to show it. I think I might use a cheap ~1.5 in lcd like this one that has a ST7789 chip and uses SPI for the picture, and a little OLED for the text and stuff like this or this, which are both controlled over I2C. I could also choose something like this larger one to display everything. I will probably control these using another Pi Pico so that the keyboard function doesn't break or slow down if this little screen does. I am glad that I found solutions for this because I was worried I wouldn't be able to get this to work.
1.75 hours
June 27: Nitty gritty
I looked at the displays again and I think I will use one display for the image and one for the text. I will probably use this for the image, and this for the text. I will control these from some RP2040 board and use this library for the text and this one for the image. I think i will use another Pi pico. It took a little while to find documented displays in the right size that didn't cost a lot, but these seem fine.
0.25 hours