how to write a makefile for c program multiple files

Will see how to place C functions and data structures in their ownįile(s) and how to incorporate them into a new program. Re-use in your own scientific programming and data analysis. Your own library of C functions and data structures, that you can other C libraries) you will have toĭeal with code that resides in multiple files. As your programs become larger, and as you start to deal eep files without this!!).The programs we have seen so far have all been stored in a single (for example it would take you a long time to work out the rule for making. That comes with a very sensible makefile_template and a program to read it and then output a target specific copy which makes things very painless. While you can learn to write your own Makefiles from scratch (if you don't want Eclipse, Studio, Code::Blocks or whatever to generate them for you) the best 'half way house' is: data proj.elf proj.hexīut to be honest you don't really want to be typing such commands all the time so most people would put all the rules to do this in a Makefile. hex from this with:Īvr-objcopy -O ihex -j.

So cross-references in the files will be linked to each other and this will finally write a fully linked copy of the code to the proj.elf output file. The absence of -c means 'don't just compile but link together the inputs'. Then you join those together using the linker:Īvr-gcc -mmcu=atmega16 file1.o file2.o file3.o -o proj.elf Which separately compiles (-c) three different files to generate ELF object files. You use:Īvr-gcc -c -mmcu=atmega16 file1.c -o file1.oĪvr-gcc -c -mmcu=atmega16 file2.c -o file2.oĪvr-gcc -c -mmcu=atmega16 file3.c -o file3.o How do I compile all of these? Thank you for you help in advance! Users/alkopop79/Documents/AVR/serial/serial.c:14: undefined reference to `transmitByte'Ĭollect2: error: ld returned 1 exit statusĪll in all I have USART.c, USART.h for serial communication and pinDefine.c for defining the pins (duh!) and of course a main. Users/alkopop79/Documents/AVR/serial/serial.c:13: undefined reference to `recieveByte' Users/alkopop79/Documents/AVR/serial/serial.c:10: undefined reference to `printString' Users/alkopop79/Documents/AVR/serial/serial.c:9: undefined reference to `initUsart' This is what I've tried so far: 'avr-gcc -g -Os -DF_CPU=16000000UL -mmcu=atmega328p -c serial.c USART.c' then 'avr-gcc -g -mmcu=atmega328p -o serial.elf serial.o' which gives me this error: c files for serial port and pin definition. However, I'm confused about compiling multiple files. I have managed to flash a blink file to an Arduino Nano successfully.

Dear all, this is literally my first day of AVR programming.

How to write a makefile for c program multiple files