This is probably a working title since I suck at giving names to things.
Ever since I started playing with 6502 SBCs, I wanted to build a SBC with a 3D-printed or acrylic case, a keyboard, an LCD display and some I/O.
I learned a lot while building multiple revisions of my Deck65 (
viewtopic.php?f=12&t=7501&p=98325#p98325), so I'm going to give a try to my larges project so far.
Internals are pretty much unchanged from my Deck65:
- 8 MHz / 2 MHz clock, ATF16V8B
- ACIA (internet access through ESP-01), VIA (I2C, SPI, PS/2 keyboard, GPIO)
- Built-in I2C RTC & I2C EEPROM
However, I'm also adding some new things:
- Built-in 48-key keyboard with Kailh Choc white switches (low-profile, clicky), powered by Atmega328P. Controls the computer through the same PS/2 interface as the external keyboard, can be disabled.
- RAM banking
- A battery would be nice! First I'll need to measure how much current does my beast draw to see if it's going to make sense to add one. But I think I'll have plenty of space for even a really large LiPo battery.
Overall, my goal is to make a fully standalone machine with everything built in, even a keyboard. (I have a lot of experience in building custom mechanical keyboards, I think I've made around 20 so far, mostly hand-wired). Here's my daily driver:
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I love the looks of transparent actylic with stainless steel - maybe eventually my SBC case will look something like it. And besides, making layered cases is very easy, since it's: for example, my keyboard case consists of 5 layers total - top and bottom are stainless steel plates (0.5" thick), and 3 middle layers are transparent acrylic. It also feels very strong and rigid - I think my keyboard can even be used as a blunt weapon!
Also It would probably be cheaper than 3D printing: we have a lot of CNC cutting places in my city, so ordering a custom set of steel or acrylic plates is very cheap (the ones in my keyboard cost me less than $10 to make).
I have experience with 2D CAD, but I really suck at 3D. Seems like FreeCAD is quite powerful and pretty popular, and most importantly - free & open-source. (Last time I did 3D modeling was probably ~18 years ago when me & my friends were making custom maps & mods for Q3 & GoldSrc engine, and probably some gamedev as a hobby several years ago).
I'm currently thinking about how to make it convenient. I initially thought of having it as a single 10" x 6.3" board (254mm x 160.02mm), but it would probably make sense to have 2 layers (same as most machines of the past - C64, TRS-80 Model 100, etc): main PCB on the bottom and keyboard/LCD at the top. As you might have guessed, Model 100 was a huge inspiration for my build.
Top view
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File comment: CORRECTION: 240x64, not 128x64
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Side view:
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JLCPCB estimates 10" x 6.3" at around $11 and I think it's a really nice price.
So I'll probably add a cut to my PCB to split it into two 10" x 3.15" boards.
My current layout looks like this:
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And once again - Dip Trace is a breeze when it comes to autorouting:
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This is not a final board - just sharing what I've done so far to hear any feedback!