For ARM7, A hardware timer is 32-bits, and unsigned int is 32-bits too; For a 16-bits MCU, A hardware timer is 16-bits, and unsigned int is 16-bits too;
So,
t0 = timer_val; while ( ( timer_val - t0 ) < delay_val );
provide a simple and good delay;
Not so sure about, if a cast is needed.
t0 = timer_val; while ( (unsigned int)( timer_val - t0 ) < delay_val );
Just noticed that, due to the integral promotion,
unsigned short t0, t1; ( t1 - t0 ) is a signed int.
It seems that,
unsigned int t0, t1; ( t1 - t0 ) is still an unsigned int.
I noticed this, because I use unsigned short to present a 16-bits timer_val on my X86-PC for testing/simulating purpose, and the result is not what I expected.
For ARM7, A hardware timer is 32-bits, and unsigned int is 32-bits too; For a 16-bits MCU, A hardware timer is 16-bits, and unsigned int is 16-bits too; this is the usual illusion that embedded code (for sure, the part touching I/O) is portable some HW timers count up, some count down, what about tyhat?
rik