8-bit AVR Microcontroller

Serial Downloading

Both the Flash and EEPROM memory arrays can be programmed using the serial SPI bus while RESET is pulled to GND. The serial interface consists of pins SCK, MOSI (input) and MISO (output). After RESET is set low, the Programming Enable instruction needs to be executed first before program/erase operations can be executed.

Note: The pin mapping for SPI programming is listed in the following section. Not all parts use the SPI pins dedicated for the internal SPI interface.