SAADC Example

RE: SAADC Example

1730143 — Thu, 21 Nov 2019 04:11:08 GMT

Thanks Jared,

i have solved this issue.

RE: SAADC Example

Jared — Tue, 19 Nov 2019 14:42:26 GMT

This would get you the time elapsed between the first call to the capture task to the second call. I'm not sure if you have a specific question or if you've solved the issue?

RE: SAADC Example

1730143 — Tue, 19 Nov 2019 14:20:56 GMT

NRF_TIMER2->TASKS_CAPTURE[1] = 1;
counter = NRF_TIMER2->CC[1];
NRF_LOG_INFO("counter:%d",counter);
stop_saadc();
start_saadc();
NRF_TIMER2->TASKS_CAPTURE[1] = 1;
counter = NRF_TIMER2->CC[1];
NRF_LOG_INFO("counter:%d",counter);

I learned that i should enable Capture task again and read the "counter" value,then subtract

thanks Jared

RE: SAADC Example

Jared — Tue, 19 Nov 2019 13:52:46 GMT

Hi,

[quote user=""]i learned in this forum that this stop_saadc function can solve the channel data shifting problem,[/quote]

Exactly which problem are you referring to? You only need to call nrf_drv_saadc_uninit to un-initialize the driver, alternatively you can also call nrf_drv_saadc_abort() to make sure that you're not un-initializing it in a middle of a conversion. See this case. Yes, you can use a timer for measuring elapsed time between function calls.

[quote user="1730143"]"counter" is always 8 , it is not right. what is right way to measure time?[/quote]

Do you mean by this that you always get 8 ticks between each time you reset the saadc?

regards

Jared

RE: SAADC Example

1730143 — Sun, 17 Nov 2019 16:50:01 GMT

Hi Nordic:

i found in this forum:

i use TASK_CAPTURE to measure time consume:

i enable TIMER2 in sdk_config.h

code:

nrf_drv_timer_config_t timer_cfg2 = NRF_DRV_TIMER_DEFAULT_CONFIG;
timer_cfg2.bit_width = NRF_TIMER_BIT_WIDTH_32;
timer_cfg2.mode = NRF_TIMER_MODE_TIMER;
err_code = nrf_drv_timer_init(&m_timer2, &timer_cfg2, timer_handler);
APP_ERROR_CHECK(err_code);

nrf_drv_timer_enable(&m_timer2);
NRF_TIMER2->TASKS_CAPTURE[1] = 1;
stop_saadc();
start_saadc();
counter = NRF_TIMER2->CC[1];
NRF_LOG_INFO("counter:%d",counter);

"counter" is always 8 , it is not right. what is right way to measure time?

thanks in advance!!