I want two pwm channel output 1MHZ frequency, the phase difference between two PWM channels is 180 degrees。when i set two pwm frequency to 500KHZ, use the configure below, the pwm is right.
nrf_drv_pwm_config_t const config0 =
{
.output_pins =
{
EMS_BRIDGE_1_PIN, // channel 0
EMS_BRIDGE_2_PIN, // channel 1
NRF_DRV_PWM_PIN_NOT_USED, // channel 2
NRF_DRV_PWM_PIN_NOT_USED // channel 3
},
.irq_priority = APP_IRQ_PRIORITY_LOWEST,
.base_clock = NRF_PWM_CLK_16MHz,
.count_mode = NRF_PWM_MODE_UP,
.top_value = 16,
.load_mode = NRF_PWM_LOAD_INDIVIDUAL,
.step_mode = NRF_PWM_STEP_AUTO
};
APP_ERROR_CHECK(nrf_drv_pwm_init(&m_pwm0, &config0, NULL));
//m_used |= USED_PWM(0);
// This array cannot be allocated on stack (hence "static") and it must
// be in RAM (hence no "const", though its content is not changed).
static nrf_pwm_values_individual_t seq_values[] =
{
0xE, 0x7FFF
};
static nrf_pwm_values_individual_t seq_values1[] =
{
0x7FFF, 0xE
};
nrf_pwm_sequence_t const seq =
{
.values.p_individual = seq_values,
.length = NRF_PWM_VALUES_LENGTH(seq_values),
.repeats = 0,
.end_delay = 0
};
nrf_pwm_sequence_t const seq1 =
{
.values.p_individual = seq_values1,
.length = NRF_PWM_VALUES_LENGTH(seq_values1),
.repeats = 0,
.end_delay = 0
};
nrf_drv_pwm_complex_playback(&m_pwm0, &seq, &seq1, 1, NRF_DRV_PWM_FLAG_LOOP);
but when i modify ".top_value = 16," to " .top_value = 8,", "seq_values[]" from "0xE, 0x7FFF" to "0x6, 0x7FFF"; and "seq_values1[]" from "0x7FFF, 0xE" to "0x7FFF, 0x6", the pwm output is not correct, just like below:
nrf_drv_pwm_config_t const config0 =
{
.output_pins =
{
EMS_BRIDGE_1_PIN, // channel 0
EMS_BRIDGE_2_PIN, // channel 1
NRF_DRV_PWM_PIN_NOT_USED, // channel 2
NRF_DRV_PWM_PIN_NOT_USED // channel 3
},
.irq_priority = APP_IRQ_PRIORITY_LOWEST,
.base_clock = NRF_PWM_CLK_16MHz,
.count_mode = NRF_PWM_MODE_UP,
.top_value = 8,
.load_mode = NRF_PWM_LOAD_INDIVIDUAL,
.step_mode = NRF_PWM_STEP_AUTO
};
APP_ERROR_CHECK(nrf_drv_pwm_init(&m_pwm0, &config0, NULL));
//m_used |= USED_PWM(0);
// This array cannot be allocated on stack (hence "static") and it must
// be in RAM (hence no "const", though its content is not changed).
static nrf_pwm_values_individual_t seq_values[] =
{
0x6, 0x7FFF
};
static nrf_pwm_values_individual_t seq_values1[] =
{
0x7FFF, 0x6
};
nrf_pwm_sequence_t const seq =
{
.values.p_individual = seq_values,
.length = NRF_PWM_VALUES_LENGTH(seq_values),
.repeats = 0,
.end_delay = 0
};
nrf_pwm_sequence_t const seq1 =
{
.values.p_individual = seq_values1,
.length = NRF_PWM_VALUES_LENGTH(seq_values1),
.repeats = 0,
.end_delay = 0
};
nrf_drv_pwm_complex_playback(&m_pwm0, &seq, &seq1, 1, NRF_DRV_PWM_FLAG_LOOP);
why?
