#if defined SSD1306_BUS_SPI && defined SSD1306_BUS_I2C
#error "Only one SSD1306 bus interface can be specified at once in ssd1306.h"
#if defined SSD1306_BUS_SPI && defined SSD1306_BUS_I2C
#error "Only one SSD1306 bus interface can be specified at once in ssd1306.h"