PT2257 - Регулятор громкости
(updated: 29 Sep 2018, 08:50:30)
Volume control PT2257 for use with Internet radio, wav player and other applications.WebKey displays the control slider. The option suppresses on and off clicks. Connection on i2c, address 0x44.
It is controlled as pwm under number 5 in the range from 0 to 50
Turning the sound off/on is possible via GPIO 139