Chao at 03:18, 2 July 2020

2020-07-02T03:18:49Z

New page

== GCC-AVR ==
* reference page: http://avr-eclipse.sourceforge.net/wiki/index.php/The_AVR_GCC_Toolchain
* command for install: sudo apt-get install gcc-avr binutils-avr gdb-avr avr-libc avrdude
# gcc-avr： complier
# avr-libc：library used when compling
# gdb-avr ：gdb reverse debug tool, against complie
# avrdude：flash tool
=== Compile ===
* generate o file from c file:
* -c Compile or assemble the source files, but do not link.
* -Os Optimize for size, -O1, Optimize.-O2 Optimize even more.
* -g Generate debugging information that can be used by avr-gdb.
>avr-gcc -g -mmcu=atmega8 -Wall -Os -c ledtest.c 
>avr-gcc -g -Os -mmcu=atmega8 -c flash.c 
>avr-gcc –mmcu=at90s2313 –c demo1.c 
* output .o .elf file for further use, for elf file, use when have more then one c file:
* -o put output into output file
>avr-gcc -g -mmcu=atmega8 -o flash.elf flash.o 
>avr-gcc -g -mmcu=atmega8 -o ledtest.out -Wl,-Map,ledtest.map ledtest.o 
* combined linked file into MCU read hex file
>avr-objcopy -j .text -j .data -O ihex flash.elf flash.hex 
>avr-objcopy -R .eeprom -O ihex ledtest.out ledtest.hex 
Above flash.elf and ledtest.out is the input file, and the second is the output file.
>avr-size ledtest.out 
Complete commands:
* avr-gcc -Os -DF_CPU=8000000 -mmcu=attiny85 -c led_flash.c
* avr-gcc -DF_CPU=8000000 -mmcu=attiny85 -o led_flash.elf led_flash.o
* avr-objcopy -O ihex led_flash.elf led_flash.hex
* rm led_flash.o
* rm led_flash.elf
==== Note ====
* DDRC = 0xFF makes all pins on PORTC as output pins
* PORTC = 0xFF makes all pins on PORTC Logic High (5V)
* PORTC = 0x00 makes all pins on PORTC Logic Low (0V)
* _delay_ms(1000) provides 1000 milliseconds delay.
* while(1) makes an infinite loop

=== Flash code ===
* Use [[avrdude]], command like: sudo avrdude -p m8 -c dragon_isp -P usb -e -U flash:w:flash.hex

[[category: AVR SDK]]

[[category: Compiler]]

GCC-AVR - Revision history

Chao at 03:18, 2 July 2020