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atmel-samd: Handle TCC2 correctly. Unlike the other TCCs its 16bit 

rather than 24bit. Setting the period for more than a 16bit number
caused the TCC to be in a weird state where resetting it would hard
crash.

Fixes #153
This commit is contained in:
Scott Shawcroft 2017-06-09 15:29:02 -07:00
parent 43881f933d
commit 9434db07b2
1 changed files with 22 additions and 3 deletions
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25
atmel-samd/common-hal/pulseio/PWMOut.c
View File

@ -35,6 +35,9 @@
#undef ENABLE
# define _TCC_SIZE(n,unused) TPASTE3(TCC,n,_SIZE),
# define TCC_SIZES { MREPEAT(TCC_INST_NUM, _TCC_SIZE, 0) }
uint32_t target_timer_frequencies[TC_INST_NUM + TCC_INST_NUM];
uint8_t timer_refcount[TC_INST_NUM + TCC_INST_NUM];
const uint16_t prescaler[8] = {1, 2, 4, 8, 16, 64, 256, 1024};
@ -55,6 +58,12 @@ void pwmout_reset(void) {
}
Tcc *tccs[TCC_INST_NUM] = TCC_INSTS;
for (int i = 0; i < TCC_INST_NUM; i++) {
// Disable the module before resetting it.
if (tccs[i]->CTRLA.bit.ENABLE == 1) {
tccs[i]->CTRLA.bit.ENABLE = 0;
while (tccs[i]->SYNCBUSY.bit.ENABLE == 1) {
}
}
tccs[i]->CTRLA.bit.SWRST = 1;
}
Tc *tcs[TC_INST_NUM] = TC_INSTS;
@ -63,6 +72,8 @@ void pwmout_reset(void) {
continue;
}
tcs[i]->COUNT16.CTRLA.bit.SWRST = 1;
while (tcs[i]->COUNT16.CTRLA.bit.SWRST == 1) {
}
}
}
@ -142,7 +153,9 @@ void common_hal_pulseio_pwmout_construct(pulseio_pwmout_obj_t* self,
if (t->is_tc) {
resolution = 16;
} else {
resolution = 24;
// TCC resolution varies so look it up.
const uint8_t _tcc_sizes[TCC_INST_NUM] = TCC_SIZES;
resolution = _tcc_sizes[index];
}
// First determine the divisor that gets us the highest resolution.
uint32_t system_clock = system_cpu_clock_get_hz();
@ -164,7 +177,10 @@ void common_hal_pulseio_pwmout_construct(pulseio_pwmout_obj_t* self,
config_tc.wave_generation = TC_WAVE_GENERATION_MATCH_PWM;
config_tc.counter_16_bit.compare_capture_channel[0] = top;
tc_init(&self->tc_instance, t->tc, &config_tc);
enum status_code status = tc_init(&self->tc_instance, t->tc, &config_tc);
if (status != STATUS_OK) {
mp_raise_RuntimeError("Failed to init timer");
}
tc_enable(&self->tc_instance);
} else {
struct tcc_config config_tcc;
@ -174,7 +190,10 @@ void common_hal_pulseio_pwmout_construct(pulseio_pwmout_obj_t* self,
config_tcc.counter.period = top;
config_tcc.compare.wave_generation = TCC_WAVE_GENERATION_SINGLE_SLOPE_PWM;
tcc_init(&self->tcc_instance, t->tcc, &config_tcc);
enum status_code status = tcc_init(&self->tcc_instance, t->tcc, &config_tcc);
if (status != STATUS_OK) {
mp_raise_RuntimeError("Failed to init timer");
}
tcc_enable(&self->tcc_instance);
}