Senoko Battery Board as a Device The Senoko battery board contains an STM32 chip, and runs its own separate operating system. The computer itself has 10 kilobytes of RAM and 64 kilobytes of storage space, where the operating system lives. This operating system is responsible for keeping the battery charged, monitoring the power button, acting as a secondary clock, and acting as a GPIO port expander. Many devices talk to one another using the Inter-Integrated Circuit bus, commonly called I2C.