i dont know why it gives undefined reference error i already attached and defined .c and .h library file and defined them. how i can get rid of this error thank you.
C:\Users\HP\AppData\Local\Temp\cceDEDJc.ltrans0.ltrans.o: In function `sendcommand(unsigned char)':
C:\Users\HP\Documents\Arduino\oled/oled.ino:199: undefined reference to `i2c_start(unsigned char)'
C:\Users\HP\AppData\Local\Temp\cceDEDJc.ltrans0.ltrans.o: In function `senddata':
C:\Users\HP\Documents\Arduino\oled/oled.ino:207: undefined reference to `i2c_start(unsigned char)'
collect2.exe: error: ld returned 1 exit status
exit status 1
Error compiling for board Arduino/Genuino Uno.
Please post your full sketch.
If possible, you should always post code directly in the forum thread as text using code tags:
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