See the previous post (here) for detailed information on AS7 installation and simulating of an Arduino program execution. As an exercise to gain familiarity with AS7, lets make an assembly language project using the below Blink code:
• Select “File>New>Project”.
• AVR Assembler Project.
• Give it a unique name.
• Select the proper device.
Remember to select the Simulator in order to run the program inside the AS7 IDE. See the previous post on how to do this. Here is a screen shot of the assembly code running in AS7:
Here is the code for a very basic assembly language blink program:
.include "m168pdef.inc" .org 0x0000 rjmp start start: ldi r16, 0 ; reset system status out SREG, r16 ; init stack pointer ldi r16, low(RAMEND) out SPL, r16 ldi r16, high(RAMEND) out SPH, r16 sbi DDRB, DDB5 ;pinMode(13, OUTPUT); _loop: sbi PORTB, PORTB5 ;turn LED on rcall _delay cbi PORTB, PORTB5 ;turn LED off rcall _delay rjmp _loop _delay: ldi r24, 0x00 ;one second delay iteration ldi r23, 0xd4 ldi r22, 0x30 _d1: ;delay ~1 second subi r24, 1 sbci r23, 0 sbci r22, 0 brcc _d1 ret
Now, start learning inline assembly language:
Also available as a book, with greatly expanded coverage!