Substitute DELAY_US macros used to implement delay

[gabrielbrunheira]

This macro blocks execution of some ISR's when executed inside other ISRs. It should be implemented by timers or other non-blocking strategy.

[gabrielbrunheira]

One weaker alternative to timers is to avoid using this macros inside blocking functions (like ISR). Instead, a non-blocking task that uses this macro could be scheduled to perform the required funcionality.