stmhal: Fix bug where negative delay/udelay lead to huge delays.

A negative ms/us is now treated as a delay of 0 ms/us.  This patch also
improves the calibration of udelay.
This commit is contained in:
Damien George 2014-05-03 14:11:56 +01:00
parent c12242e9df
commit bff1ff28ee
1 changed files with 12 additions and 8 deletions

View File

@ -143,22 +143,26 @@ STATIC MP_DEFINE_CONST_FUN_OBJ_0(pyb_millis_obj, pyb_millis);
/// \function delay(ms)
/// Delay for the given number of milliseconds.
STATIC mp_obj_t pyb_delay(mp_obj_t count) {
HAL_Delay(mp_obj_get_int(count));
STATIC mp_obj_t pyb_delay(mp_obj_t ms_in) {
machine_int_t ms = mp_obj_get_int(ms_in);
if (ms >= 0) {
HAL_Delay(ms);
}
return mp_const_none;
}
STATIC MP_DEFINE_CONST_FUN_OBJ_1(pyb_delay_obj, pyb_delay);
/// \function udelay(us)
/// Delay for the given number of microseconds.
STATIC mp_obj_t pyb_udelay(mp_obj_t usec) {
uint32_t count = 0;
const uint32_t utime = (168 * mp_obj_get_int(usec) / 5);
for (;;) {
if (++count > utime) {
return mp_const_none;
STATIC mp_obj_t pyb_udelay(mp_obj_t usec_in) {
machine_int_t usec = mp_obj_get_int(usec_in);
if (usec > 0) {
uint32_t count = 0;
const uint32_t utime = (168 * usec / 4);
while (++count <= utime) {
}
}
return mp_const_none;
}
STATIC MP_DEFINE_CONST_FUN_OBJ_1(pyb_udelay_obj, pyb_udelay);