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Merged
nedseb merged 14 commits into from
Apr 16, 2026
Merged

feat(bq27441): Add battery pet (tamagotchi) example with OLED. #399

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fa3a251
feat: Initialize Tamagotchi game with needs system and health mechanic.
DumontALINE Apr 14, 2026
11750ef
feat: Add first character sprites in different situations.
DumontALINE Apr 15, 2026
166cbd6
feat: Add a Tamagotchi aging system based on battery percentage.
DumontALINE Apr 15, 2026
7d1119d
refactor: Move file to correct directory.
DumontALINE Apr 15, 2026
ce8b6bc
feat: Add sound effects to the Tamagotchi.
DumontALINE Apr 15, 2026
c77a01e
chore: Fix code with ruff.
DumontALINE Apr 16, 2026
307a55f
chore: Remove debugging code.
DumontALINE Apr 16, 2026
5c2da76
refactor: Fix typos, move sound dict, add buzzer cleanup.
DumontALINE Apr 16, 2026
c823af8
style: Fix ruff E201/E231 lint errors in sprite arrays.
DumontALINE Apr 16, 2026
fd04b5f
fix: Fix lint E221 and invisible text on GS4 OLED.
DumontALINE Apr 16, 2026
83fb146
fix: Fix SPRITE_BASE formatting to comply with ruff E201/E231.
DumontALINE Apr 16, 2026
2a5375c
fix: Remove redundant upper bound in charge elif condition.
DumontALINE Apr 16, 2026
21c8f9d
fix: Fix ruff linting errors.
DumontALINE Apr 16, 2026
e362948
fix(bq27441): Fix tamagotchi example naming, logic and style.
nedseb Apr 16, 2026
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353 changes: 353 additions & 0 deletions lib/bq27441/examples/tamagotchi.py
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"""Battery Tamagotchi example using BQ27441, MCP23009E D-PAD, SSD1327 OLED and buzzer.

The creature ages based on the real battery percentage and periodically asks
to be fed or played with via the D-PAD. A correct answer triggers a happy
sprite + success sound; a wrong or missed answer triggers an angry sprite +
fail sound. When the battery drops below 10 %, the game is over.

Controls:
UP / DOWN -> navigate the action menu
LEFT -> confirm selection
"""

import random
from time import sleep_ms, ticks_diff, ticks_ms

import ssd1327
from bq27441 import BQ27441
from machine import I2C, SPI, Pin
from mcp23009e import MCP23009E
from mcp23009e.const import (
MCP23009_BTN_DOWN,
MCP23009_BTN_LEFT,
MCP23009_BTN_RIGHT,
MCP23009_BTN_UP,
MCP23009_DIR_INPUT,
MCP23009_I2C_ADDR,
MCP23009_LOGIC_LOW,
MCP23009_PULLUP,
)
from pyb import Timer

# --- Hardware setup ---

spi = SPI(1)
dc = Pin("DATA_COMMAND_DISPLAY")
res = Pin("RST_DISPLAY")
cs = Pin("CS_DISPLAY")
display = ssd1327.WS_OLED_128X128_SPI(spi, dc, res, cs)

i2c = I2C(1)
reset_expander = Pin("RST_EXPANDER", Pin.OUT)
mcp = MCP23009E(i2c, address=MCP23009_I2C_ADDR, reset_pin=reset_expander)

fg = BQ27441(i2c)

buzzer_tim = Timer(1, freq=1000)
buzzer_ch = buzzer_tim.channel(4, Timer.PWM, pin=Pin("SPEAKER"))
buzzer_ch.pulse_width_percent(0)

# --- Constants ---

BUTTONS = {
MCP23009_BTN_UP: "UP",
MCP23009_BTN_DOWN: "DOWN",
MCP23009_BTN_LEFT: "LEFT",
MCP23009_BTN_RIGHT: "RIGHT",
}

ACTION = ["food", "play"]
NEED = ["I'm bored", "I'm hungry"]

IDLE_DISPLAY_MS = 1000
RESPONSE_TIMEOUT_MS = 5000
RESULT_DISPLAY_MS = 1000

X0 = 35
ITEM_Y = 100
ITEM_SPACING = 14

# --- Sprites ---

SPRITE_BASE = [
[0, 0, 15, 15, 0, 0, 0, 0, 0, 15, 15, 0, 0],
[0, 15, 15, 15, 15, 0, 0, 0, 15, 15, 15, 15, 0],
[0, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 0],
[0, 15, 15, 0, 0, 0, 0, 0, 0, 0, 15, 15, 0],
[0, 15, 0, 0, 15, 0, 0, 0, 15, 0, 0, 15, 0],
[15, 0, 0, 0, 0, 15, 15, 15, 0, 0, 0, 0, 15],
[15, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 15],
[0, 15, 0, 0, 0, 0, 0, 0, 0, 0, 0, 15, 0],
[15, 0, 0, 15, 0, 0, 0, 0, 0, 15, 0, 15, 0],
[0, 15, 15, 0, 0, 0, 0, 0, 0, 15, 15, 15, 0],
[0, 15, 0, 0, 0, 0, 0, 0, 0, 0, 0, 15, 0],
[0, 0, 15, 0, 0, 0, 0, 0, 0, 0, 15, 0, 0],
[0, 0, 0, 15, 0, 15, 15, 15, 0, 15, 0, 0, 0],
[0, 0, 0, 15, 0, 15, 0, 15, 0, 15, 0, 0, 0],
[0, 0, 0, 0, 15, 0, 0, 0, 15, 0, 0, 0, 0],
]

SPRITE_HUNGRY = [
[0, 0, 15, 15, 0, 0, 0, 0, 0, 15, 15, 0, 0],
[0, 15, 15, 15, 15, 0, 0, 0, 15, 15, 15, 15, 0],
[0, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 0],
[0, 15, 15, 0, 0, 0, 0, 0, 0, 0, 15, 15, 0],
[0, 15, 0, 0, 15, 0, 0, 0, 15, 0, 0, 15, 0],
[15, 0, 0, 0, 0, 15, 15, 15, 0, 0, 0, 0, 15],
[15, 0, 0, 0, 0, 15, 15, 15, 0, 0, 0, 0, 15],
[0, 15, 0, 0, 0, 15, 15, 15, 0, 0, 0, 15, 0],
[15, 0, 0, 15, 0, 0, 0, 0, 0, 15, 0, 15, 0],
[0, 15, 15, 0, 0, 0, 0, 0, 0, 15, 15, 15, 0],
[0, 15, 0, 0, 0, 0, 0, 0, 0, 0, 0, 15, 0],
[0, 0, 15, 0, 0, 0, 0, 0, 0, 0, 15, 0, 0],
[0, 0, 0, 15, 0, 15, 15, 15, 0, 15, 0, 0, 0],
[0, 0, 0, 15, 0, 15, 0, 15, 0, 15, 0, 0, 0],
[0, 0, 0, 0, 15, 0, 0, 0, 15, 0, 0, 0, 0],
]

SPRITE_SAD = [
[0, 0, 15, 15, 0, 0, 0, 0, 0, 15, 15, 0, 0],
[0, 15, 15, 15, 15, 0, 0, 0, 15, 15, 15, 15, 0],
[0, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 0],
[0, 15, 15, 0, 0, 0, 0, 0, 0, 0, 15, 15, 0],
[0, 15, 0, 15, 15, 0, 0, 0, 15, 15, 0, 15, 0],
[15, 0, 0, 0, 0, 0, 15, 0, 0, 0, 0, 0, 15],
[15, 0, 0, 0, 0, 15, 0, 15, 0, 0, 0, 0, 15],
[0, 15, 0, 0, 0, 0, 0, 0, 0, 0, 0, 15, 0],
[15, 0, 0, 15, 0, 0, 0, 0, 0, 15, 0, 15, 0],
[0, 15, 15, 0, 0, 0, 0, 0, 0, 15, 15, 15, 0],
[0, 15, 0, 0, 0, 0, 0, 0, 0, 0, 0, 15, 0],
[0, 0, 15, 0, 0, 0, 0, 0, 0, 0, 15, 0, 0],
[0, 0, 0, 15, 0, 15, 15, 15, 0, 15, 0, 0, 0],
[0, 0, 0, 15, 0, 15, 0, 15, 0, 15, 0, 0, 0],
[0, 0, 0, 0, 15, 0, 0, 0, 15, 0, 0, 0, 0],
]

SPRITE_HAPPY = [
[0, 0, 15, 15, 0, 0, 0, 0, 0, 15, 15, 0, 0],
[0, 15, 15, 15, 15, 0, 0, 0, 15, 15, 15, 15, 0],
[0, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 0],
[0, 15, 15, 0, 0, 0, 0, 0, 0, 0, 15, 15, 0],
[0, 15, 0, 0, 15, 0, 0, 0, 15, 0, 0, 15, 0],
[15, 0, 0, 15, 0, 15, 0, 15, 0, 15, 0, 0, 15],
[15, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 15],
[0, 15, 0, 0, 0, 15, 15, 15, 0, 0, 0, 15, 0],
[15, 0, 0, 15, 0, 0, 0, 0, 0, 15, 0, 15, 0],
[0, 15, 15, 0, 0, 0, 0, 0, 0, 15, 15, 15, 0],
[0, 15, 0, 0, 0, 0, 0, 0, 0, 0, 0, 15, 0],
[0, 0, 15, 0, 0, 0, 0, 0, 0, 0, 15, 0, 0],
[0, 0, 0, 15, 0, 15, 15, 15, 0, 15, 0, 0, 0],
[0, 0, 0, 15, 0, 15, 0, 15, 0, 15, 0, 0, 0],
[0, 0, 0, 0, 15, 0, 0, 0, 15, 0, 0, 0, 0],
]

SPRITE_ANGRY = [
[0, 0, 15, 15, 0, 0, 0, 0, 0, 15, 15, 0, 0],
[0, 15, 15, 15, 15, 0, 0, 0, 15, 15, 15, 15, 0],
[0, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 0],
[0, 15, 15, 0, 0, 0, 0, 0, 0, 0, 15, 15, 0],
[0, 15, 0, 15, 0, 0, 0, 0, 0, 15, 0, 15, 0],
[15, 0, 0, 0, 15, 0, 0, 0, 15, 0, 0, 0, 15],
[15, 0, 0, 0, 0, 0, 15, 0, 0, 0, 0, 0, 15],
[0, 15, 0, 0, 0, 15, 0, 15, 0, 0, 0, 15, 0],
[15, 0, 0, 15, 0, 0, 0, 0, 0, 15, 0, 15, 0],
[0, 15, 15, 0, 0, 0, 0, 0, 0, 15, 15, 15, 0],
[0, 15, 0, 0, 0, 0, 0, 0, 0, 0, 0, 15, 0],
[0, 0, 15, 0, 0, 0, 0, 0, 0, 0, 15, 0, 0],
[0, 0, 0, 15, 0, 15, 15, 15, 0, 15, 0, 0, 0],
[0, 0, 0, 15, 0, 15, 0, 15, 0, 15, 0, 0, 0],
[0, 0, 0, 0, 15, 0, 0, 0, 15, 0, 0, 0, 0],
]

SPRITE_DEAD = [
[0, 0, 0, 0, 0, 0, 15, 15, 15, 15, 15, 15, 0, 0, 0, 0, 0],
[0, 0, 0, 0, 15, 15, 0, 0, 0, 0, 0, 0, 15, 15, 0, 0, 0],
[0, 0, 0, 15, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 15, 0, 0],
[0, 0, 15, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 15, 0],
[0, 0, 15, 0, 0, 0, 0, 0, 0, 0, 0, 15, 0, 15, 0, 15, 0],
[0, 15, 0, 0, 15, 15, 0, 0, 0, 0, 0, 15, 0, 15, 0, 0, 15],
[0, 15, 0, 15, 0, 0, 15, 0, 0, 0, 0, 0, 0, 0, 0, 0, 15],
[0, 15, 0, 15, 0, 0, 0, 0, 0, 0, 15, 0, 15, 0, 15, 0, 15],
[15, 0, 0, 0, 15, 0, 0, 0, 0, 0, 15, 15, 15, 15, 15, 0, 15],
[15, 0, 0, 0, 0, 0, 0, 0, 0, 0, 15, 15, 15, 15, 15, 0, 15],
[15, 0, 0, 0, 0, 0, 0, 0, 0, 15, 15, 15, 15, 15, 0, 15, 0],
[0, 15, 0, 0, 0, 0, 0, 0, 0, 15, 0, 15, 0, 15, 0, 15, 0],
[0, 0, 15, 15, 15, 0, 0, 0, 0, 0, 0, 0, 0, 0, 15, 0, 0],
[0, 0, 0, 0, 0, 15, 15, 0, 0, 0, 0, 15, 15, 15, 0, 0, 0],
[0, 0, 0, 0, 0, 0, 0, 15, 15, 15, 15, 0, 0, 0, 0, 0, 0],
]

# --- Sounds ---

SOUND = {
"start": [
(523, 120),
(659, 120),
(784, 120),
(1047, 400),
],
"hungry": [
(400, 150),
(350, 150),
(300, 300),
],
"bored": [
(500, 120),
(650, 120),
(800, 200),
],
"success": [
(600, 100),
(800, 100),
(1000, 200),
],
"fail": [
(500, 150),
(400, 150),
(300, 400),
],
}

# --- Helpers ---


def setup_buttons():
"""Configure all D-PAD buttons as inputs with pull-ups."""
for pin_number in BUTTONS:
mcp.setup(pin_number, MCP23009_DIR_INPUT, pullup=MCP23009_PULLUP)


def wait_for_button():
"""Poll D-PAD once and return the pressed button name, or None."""
for pin_number, name in BUTTONS.items():
if mcp.get_level(pin_number) == MCP23009_LOGIC_LOW:
while mcp.get_level(pin_number) == MCP23009_LOGIC_LOW:
sleep_ms(20)
return name
return None


def draw_character(cx, cy, scale, sprite):
"""Draw a scaled pixel-art sprite on the display framebuf."""
fb = display.framebuf
for y, row in enumerate(sprite):
for x, color in enumerate(row):
for dy in range(scale):
for dx in range(scale):
fb.pixel(cx + x * scale + dx, cy + y * scale + dy, color)


def create_screen(selected_index, need, sprite, charge):
"""Render one game frame: sprite, need text, charge and action menu."""
display.fill(0)
display.text(need, 25, 20, 15)
display.text(str(charge), 50, 10, 15)

if charge >= 70:
scale, x, y = 1, 55, 60
elif charge >= 40:
scale, x, y = 2, 45, 50
else:
scale, x, y = 3, 40, 40

draw_character(x, y, scale, sprite)

for index, label in enumerate(ACTION):
row_y = ITEM_Y + index * ITEM_SPACING
prefix = ">" if index == selected_index else " "
display.text(prefix + label, X0, row_y, 15)

display.show()


def create_game_over_screen():
"""Display the game-over screen."""
display.fill(0)
display.text("Game Over", 25, 20, 15)
draw_character(35, 45, 3, SPRITE_DEAD)
display.show()


def action_check(selected_index, need):
"""Check if the selected action matches the current need."""
name = ACTION[selected_index]
return (need == "I'm bored" and name == "play") or (need == "I'm hungry" and name == "food")


def sound_effect(name):
"""Play a short melody from the SOUND dictionary."""
for freq, duration_ms in SOUND[name]:
buzzer_tim.freq(freq)
buzzer_ch.pulse_width_percent(10)
sleep_ms(duration_ms)
buzzer_ch.pulse_width_percent(0)
sleep_ms(30)


# --- Main game loop ---


def main():
"""Run the Tamagotchi game."""
setup_buttons()
sound_effect("start")
is_alive = True

try:
while is_alive:
selected_index = 0
charge = fg.state_of_charge()

# Idle phase
create_screen(selected_index, " ", SPRITE_BASE, charge)
sleep_ms(IDLE_DISPLAY_MS)

# Need phase
need = random.choice(NEED)
if need == "I'm bored":
sprite = SPRITE_SAD
sound_effect("bored")
else:
sprite = SPRITE_HUNGRY
sound_effect("hungry")

create_screen(selected_index, need, sprite, charge)

# Response phase
start = ticks_ms()
win = None

while True:
elapsed = ticks_diff(ticks_ms(), start)
if elapsed >= RESPONSE_TIMEOUT_MS:
break

button = wait_for_button()
if button == "UP":
selected_index = (selected_index - 1) % len(ACTION)
create_screen(selected_index, need, sprite, charge)
elif button == "DOWN":
selected_index = (selected_index + 1) % len(ACTION)
create_screen(selected_index, need, sprite, charge)
elif button == "LEFT":
win = action_check(selected_index, need)
break
sleep_ms(20)

# Result phase
if win:
create_screen(selected_index, need, SPRITE_HAPPY, charge)
sound_effect("success")
else:
create_screen(selected_index, need, SPRITE_ANGRY, charge)
sound_effect("fail")
sleep_ms(RESULT_DISPLAY_MS)

if charge < 10:
is_alive = False
create_game_over_screen()
finally:
buzzer_ch.pulse_width_percent(0)


main()
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