How to covert APP_TIMER ticks to MS

Question

I am trying to record the time on nRF52840 with s140 softdevice.
I used APP_TIMER to setup the TIMER and app_timer_cnt_get to get the count. And then uint32_t app_timer_cnt_diff_compute(uint32_t ticks_to, uint32_t ticks_from); to get the ticks for the time span.
However, I am confused about how to get the actual time. There is not defined ticks to time macro in app_timer.h .
I read some discussion about this and the solution is like 
 
 APP_TIMER_TICKS = ( MS * APP_TIMER_CLOCK_FREQ ) / ( ( PRESCALAR + 1 ) * 1000 ) 
 
 But in SDK 14.0 the macro for time to ticks is like 
 #ifndef FREERTOS
#define APP_TIMER_TICKS(MS) \
 ((uint32_t)ROUNDED_DIV( \
 (MS) * (uint64_t)APP_TIMER_CLOCK_FREQ, \
 1000 * (APP_TIMER_CONFIG_RTC_FREQUENCY + 1)))
#else
#include "FreeRTOSConfig.h"
#define APP_TIMER_TICKS(MS) (uint32_t)ROUNDED_DIV((MS)*configTICK_RATE_HZ,1000)
#endif
 
 I don't know in SDK 14 the safe way to convert ticks to time anymore.

Joakim Jakobsen · Accepted Answer

Hi mich_x! 
 The macro in SDK v14. is the same as the one above. Take a look at this site for more information. 
 You can also take a look at my answer in this case , as it should provide some useful information. 
 However, in your case, lets make an example. If you use the macro in SDK v14, with a prescaler of 1 and 1000ms. 
 APP_TIMER_TICKS = (1000 * 32768) / ((1 + 1) * 1000) = 16384 ticks. 
 
 This means that when you use the app_timer_cnt_get and the value is 16384, 1000ms has passed. 
 Hope that cleared things up a bit. Let me know if something is unclear. 
Best regards, 
Joakim.

How to covert APP_TIMER ticks to MS

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