mruby/c sources for aqm0802a (LCD module)
https://akizukidenshi.com/catalog/g/gP-06669/
https://akizukidenshi.com/download/ds/xiamen/AQM0802.pdf
LCD と RTC を使う場合の例
#I2C 初期化
i2c = I2C.new()
# LCD 初期化
lcd = AQM0802A.new(i2c)
# LCD に "Hello World" 表示
lcd.cursor(0, 0)
lcd.write_string("Hello?!")
lcd.cursor(0, 1)
lcd.write_string("from ESP")