I want to get vdd without timer
so i found this.
https://devzone.nordicsemi.com/f/nordic-q-a/38239/nrf-52832-saadc-without-timer/147517#147517
and change some part like this
void saadc_event_handler(nrf_drv_saadc_evt_t const * p_event) {
// Do nothing, as we use blocking mode
}
int saadc_init() {
int ret = nrf_drv_saadc_init(NULL, saadc_event_handler);
if (ret) return ret;
nrf_saadc_channel_config_t config =
NRF_DRV_SAADC_DEFAULT_CHANNEL_CONFIG_SE(NRF_SAADC_INPUT_VDD);
ret = nrf_drv_saadc_channel_init(0, &config);
return ret;
}
int saadc_measure() {
nrf_saadc_value_t value;
nrf_drv_saadc_sample_convert(0, &value);
return value;
}
int main() {
saadc_init();
NRF_LOG_INFO("THIS IS DIRECTLY :%d.",saadc_measure());
}
but nothing was printed
so I try this
..
..
..
..
void saadc_sampling_event_init(void)
{
ret_code_t err_code;
err_code = nrf_drv_ppi_init();
APP_ERROR_CHECK(err_code);
nrf_drv_timer_config_t timer_cfg = NRF_DRV_TIMER_DEFAULT_CONFIG;
timer_cfg.bit_width = NRF_TIMER_BIT_WIDTH_32;
err_code = nrf_drv_timer_init(&m_timer, &timer_cfg, timer_handler);
APP_ERROR_CHECK(err_code);
/* setup m_timer for compare event every 400ms */
uint32_t ticks = nrf_drv_timer_ms_to_ticks(&m_timer, 400);
nrf_drv_timer_extended_compare(&m_timer,
NRF_TIMER_CC_CHANNEL0,
ticks,
NRF_TIMER_SHORT_COMPARE0_CLEAR_MASK,
false);
nrf_drv_timer_enable(&m_timer);
uint32_t timer_compare_event_addr = nrf_drv_timer_compare_event_address_get(&m_timer,
NRF_TIMER_CC_CHANNEL0);
uint32_t saadc_sample_task_addr = nrf_drv_saadc_sample_task_get();
/* setup ppi channel so that timer compare event is triggering sample task in SAADC */
err_code = nrf_drv_ppi_channel_alloc(&m_ppi_channel);
APP_ERROR_CHECK(err_code);
err_code = nrf_drv_ppi_channel_assign(m_ppi_channel,
timer_compare_event_addr,
saadc_sample_task_addr);
APP_ERROR_CHECK(err_code);
}
void saadc_sampling_event_enable(void)
{
ret_code_t err_code = nrf_drv_ppi_channel_enable(m_ppi_channel);
APP_ERROR_CHECK(err_code);
}
int saadc_measure() {
nrf_saadc_value_t value;
nrf_drv_saadc_sample_convert(0, &value);
return value;
}
void saadc_callback(nrf_drv_saadc_evt_t const * p_event)
{
if (p_event->type == NRF_DRV_SAADC_EVT_DONE)
{
ret_code_t err_code;
err_code = nrf_drv_saadc_buffer_convert(p_event->data.done.p_buffer, SAMPLES_IN_BUFFER);
APP_ERROR_CHECK(err_code);
int i;
NRF_LOG_INFO("ADC event number: %d", (int)m_adc_evt_counter);
for (i = 0; i < SAMPLES_IN_BUFFER; i++)
{
NRF_LOG_INFO("%d", p_event->data.done.p_buffer[i]); //data.done.p_buffer[i] 이곳에 값이 들어있음
}
m_adc_evt_counter++;
}
}
void saadc_init(void)
{
ret_code_t err_code;
nrf_saadc_channel_config_t channel_config =
NRF_DRV_SAADC_DEFAULT_CHANNEL_CONFIG_SE(NRF_SAADC_INPUT_VDD);
err_code = nrf_drv_saadc_init(NULL, saadc_callback);
APP_ERROR_CHECK(err_code);
err_code = nrf_drv_saadc_channel_init(0, &channel_config);
APP_ERROR_CHECK(err_code);
err_code = nrf_drv_saadc_buffer_convert(m_buffer_pool[0], SAMPLES_IN_BUFFER);
APP_ERROR_CHECK(err_code);
err_code = nrf_drv_saadc_buffer_convert(m_buffer_pool[1], SAMPLES_IN_BUFFER);
APP_ERROR_CHECK(err_code);
}
int main(void)
{
uint32_t err_code = NRF_LOG_INIT(NULL);
APP_ERROR_CHECK(err_code);
NRF_LOG_DEFAULT_BACKENDS_INIT();
ret_code_t ret_code = nrf_pwr_mgmt_init();
APP_ERROR_CHECK(ret_code);
saadc_init();
saadc_sampling_event_init();
saadc_sampling_event_enable();
NRF_LOG_INFO("SAADC HAL simple example started.");
while (1)
{
nrf_pwr_mgmt_run();
NRF_LOG_INFO("THIS IS DIRECTLY :%d.",saadc_measure());
NRF_LOG_FLUSH();
nrf_delay_ms(1000);
}
}
and i get this result
is this value(app:THIS~~:104) correct?
why is it different compare to 9xx ? is it because of gain? or reference?
and how to modify code to see result in jlink?
thank you for reading this :)
