Monbit

A tiny ESP32-based digital monster pet with an e-ink display that evolves over time based on care, sleep cycles, and randomness.

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Roadmap

0.0.1 — Hello Hardware

Goal

• ESP32 boots
• Serial prints work
• Display shows something
• Battery powers device
• Device can charge via USB-C

Hardware

• ESP32-C3 Development Board (WiFi + Bluetooth)
• WeAct 1.54" E-Paper Module (SPI, Black/White)
• Li-Po Battery 503035 500mAh 3.7V JST-PH 2.0
• USB-C TP4056 Lithium Battery Charger Module

Done When

• Code uploads successfully
• Serial output works
• Display shows text or image
• Device runs from battery

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0.0.2 — Input System

Goal

• Wire buttons
• Wire power switch
• Detect button presses

Hardware

• SKRGAED010 ALPS Tact Switch (or similar)

Done When

• Buttons log presses
• Switch turns device on/off

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0.0.3 — Memory System

Goal

• Save current state
• Load saved state

Done When

• Restart device
• State persists

Example:

• Hunger
• Happiness
• Energy

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0.0.4 — Sound System

Goal

• Play simple sounds
• Confirm actions with sound

Hardware

• MAX98357A Audio Amplifier Module
• 15x3.5mm Mini Round Speaker 8Ω 0.5W

Done When

• Device plays beep sound
• Sound triggered by button press

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0.0.5 — Power Optimization

Goal

• Deep sleep support
• Wake on button press
• Battery optimization

Done When

• Device sleeps automatically
• Button wakes device

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0.0.6 — First Monster Logic

Goal

• Basic monster stats
• Simple interactions

Example Stats

• Hunger
• Happiness
• Energy

Done When

• Buttons modify stats
• Display updates values

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0.0.7 — UI Improvements

Goal

• Basic UI layout
• Icons and sprites
• Monster display

Done When

• UI readable
• Monster visible

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0.1.0 — First Prototype

Goal

• Fully assembled device
• 3D printed enclosure
• Stable hardware

Done When

• Portable device
• Battery powered
• Fully functional