This is not pure C++. It looks like somebody has written either a compiler extension or a series of macros to allow the specification of pre- and post-conditions for a block of code. You’re going to have to ask that person. (As an aside, this is why just “extracting code” is often insufficient for understanding; … Read more
error messages like avr-gcc: No such file or directory Indicate 1 of several things the executable avr-gcc is not installed (properly) and/or the PATH env var does not include the directory that holds the executable the makefile was called incorrectly. Others Here are some things to try When you say “downloaded the makefile”, is that … Read more
Do the two lines have same effect of writing one to data register B ? No. DDRB = 0b00000001; writes one to bit-0 and zero to bits 1 to 7, while: DDRB |= 0b00000001; is a read-modify-write operation equivalent to: DDRB = DDRB | 0b00000001; so it writes a one to bit-0 as before and … Read more