Bill of Materials

A project log for Pomodachi

A Hardware Pomodoro Timer Virtual Pet

droxpopulidroxpopuli 07/19/2021 at 02:510 Comments

As of this Log this is the Current Bill of Materials:

* 1x HalloWing M4 Express - [$39.95 @ Adafruit](  

The core of the build with the display, processing and connectivity all coming from here.

* 1x Neokey 2 FeatherWing - [$4.50 @ Adafruit](
* 1x Mini Oval 1W 8 OHM Speaker - [$1.95 @ Adafruit](
* 2x Kaith Mechanical Keys, White - [$6.95 @ Adafruit](
* 2x Translucent MX Keycaps - [$4.95 @ Adafruit](  

A little speaker and a pair of tactile mechanical keyboard keys for I/O. Chosen as the Pomodoro technique requires a distinct sensory experience when setting a timer to work most effectively. The speaker allows for ~~annoying alarms~~ cute sounds (but not being used right now :( ).

* 1x Adafruit PCF8523 Real Time Clock Assembled Breakout Board - [$4.95 @ Adafruit](
* 1x CR1220 12mm Diameter - 3V Lithium Coin Cell Battery - [$0.95 @ Adafruit](  

Virtual pets need an RTC to allow for accurate time telling, and tracking time differences between boots

* 1x Enclosure, 3D printed from primarily [Hatchbox PLA, Beige]( and [eSun PLA+, Black]( for the face panel
* 1x Convex Glass Lens with Edge - 40mm Diameter - [$5.95 @Adafruit](
* 1x Clear Acrylic Lens Holder + Hardware Kit for HalloWing (we use the screws and spacers for mounting) - [$2.95 @ Adafruit](
* Various Metric Screw hardware TBD  

The enclosure gives this project all of its personality. The PyPortal-based case makes way for a convex glass lens that gives a nice retro effect.

* 1x Micro-USB Cable - [$4.95 @ Adafruit](
* Male-to-Female Jumpers (or other sufficient wiring) [$3.95 @ Adafruit](
* 1x Lithium Ion Polymer Battery - 3.7v 500mAh - [$7.95 @ Adafruit](  

Battery is optional but it adds weight and allows for off the desk use for short periods of time.

Total: Around $125-175 depending on what you have on hand in terms of metric screws, filament, etc.