diff --git a/ssd1306.h b/ssd1306.h
--- a/ssd1306.h
+++ b/ssd1306.h
@@ -20,6 +20,8 @@
 //#define   SPI_SendByte(data)  SPI_I2S_SendData(SPI1,data) 
 //#define   SPI_Wait()       while(!(SPI1->SR&SPI_FLAG_TXE));while(SPI1->SR&SPI_FLAG_BSY); 
 
+#include "stm32f0xx_hal_conf.h"
+
 void ssd1306_init(void);
 void ssd1306_drawchar(char ascii, unsigned char row, unsigned char xPos);
 void ssd1306_drawcharbig(char ascii, unsigned char row, unsigned char xPos);