The most common one used to be the uart bootloader .

最普通的一种通常是uartbootloader。

Basically , the way it works is similar to any bootloader , but instead of listening to uart / usb it tries to read data from an attached eeprom memory with an i2c or spi interface .

它们的基本工作原理和其他bootloader差不多，只是相比于监听uart/usb，它试图从系统附加的带i2c或spi接口的eeprom读取数据。