Firmware Version 2.2 (August 6, 2024)
Adds a sleep mode for low power consumption (hold down both buttons past firmware reading until you hear a beep; to wake up hold the settings button).
SonoAlti_3V_Firmware_2_2.uf2

Flash Revealer: SonoAlti_3V_16MB_Flash_Revealer.uf2
Flash Eraser: SonoAlti_3V_Flash_Eraser.uf2
SonoAlti 3V Sounds: SonoAlti_3V_Sounds.zip