WP32 McCake 5.25" bay
Please read the disclaimer before consdering to use this.
This is a 5.25" bay for retro PCs that use the https://www.serdashop.com/ WP32 McCake https://github.com/dwhinham/mt32-pi waveblaster extension. Be aware that Serdaco offers their own bay. This bay is a DIY alternative with a larger display and a rotary knob for volume control.
Bay + PCB have been tested and seem to work well.
You need a soldering iron, some solder and a 3D printer to build this. It is very generally easy to build. The PCB for the front panel can be ordered, for example, from jlcpcb.com, pcbway, oshpark or similar servies.
- Schematic (TODO)
- PCB Layout (TODO)
- Gerber
There is no knob for the rotary encoder in the STL directory. I have just grabbed one from thingiverse for it.
Parts are mostly standard parts and can based obtained easily from AliExpress or any other electronics dealer.
| Quantity | Part | Examples | Comments |
|---|---|---|---|
| 1 | Through-hole rotary knob with button | ||
| 2 | Through-hole standard 4-pin buttons | ||
| 1 | 2.54mm pin header with 9 pins | ||
| 1 | 1.3" SH1106 I2C OLED display (not the typical 0.96" one!) | AliExpress | Required pin order: VCC-GND-SCL-SDA |
| 1 | IDC cable with at least 9 pins in a row | Amazon | |
| 1 | Serdaco WP32 McCake |
These are the changes I have made to my mt32-pi.cfg
[system]
usb = off
[audio]
output_device = i2s
[control]
scheme = simple_encoder
[lcd]
type = sh1106_i2c
width = 128
height = 64
config.txt:
avoid_warnings=2
[pi4]
arm_64bit=1
armstub=armstub8-rpi4.bin
kernel=kernel8-rpi4.img
# Optimized frequency settings for lower energy use/temperature on Pi 4
arm_freq=600
arm_freq_min=100
gpu_freq=100
over_voltage=-16
over_voltage_min=-16
The pi4 section should be the default one starting mt32-pi 0.10.0 or so. Make sure you have the arm frequency adjustments in there in order to avoid high temperatures and throttling of the compute module 4.
The project is open-source and DIY. It is easy to build even for beginners. I do not build this for others.