blob: 5372ac1d39bee968833e46fd443b6694a9ad0f9f (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
|
/**
* @brief Delay implementation
*/
#ifndef _DELAY_H_
#define _DELAY_H_
static inline void delay_us(uint32 us) {
/* TODO this makes unwarranted assumptions about the RCC
* config; add a hook so users can make their own decisions. */
/* So (2^32)/12 micros max, or less than 6 minutes */
us *= 12;
/* fudge for function call overhead */
us--;
asm volatile(" mov r0, %[us] \n\t"
"1: subs r0, #1 \n\t"
" bhi 1b \n\t"
:
: [us] "r" (us)
: "r0");
}
#endif
|
