Finished hardware assembly and some software. I'm pretty happy with the result.
I have the center array charlieplexed. In the movie, only one red LED is on per column, so it won't get too dim. The eyes and bar arrays are driven by serial shift registers. I also included a buzzer in case I ever get the software running well enough to play a tune from the movie. Maybe digitized voice eventually? But that could be taxing the Arduino too much.
And obligatory photo with the IMSAI 8080 clone.
I tried to make the eyes update similar to the movie. The center array needs more work to make it more movie-like. I assume it was taken from an old graphic equalizer display, so it's a somewhat continuous line.
I won't show the back side because it's loaded with bodge wires. I learned not to solder on LEDs, and then clip off the leads. It broke a few of the traces at the through-hole pad. I could also reinforce them with some large teardrops going into the pad. I also had my MISO and MOSI swapped. The bit-banged SPI was not fast enough and showed a noticeable flicker, so I had to rewire it.
For the released layout I need to make some changes:
- Swap MISO and MOSI
- Increase reference designator text size
- Change SOIC footprint to include SOP package size for shift registers
- Change SMT resistor array to an SOIC package for easier soldering
- Put long lead/short lead indicators in silk screen for easier assembly
- Add 3.3V and 5.0V test points
- Add teardrops at through-hole locations to lower risk of breaking
Now just need to make some kind of a case for it.
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