There isn't really a good way to calibrate this RTC adafruit#1046

nickzoic · nickzoic · commit 6afe23d0b0e4 · 2019-04-02T13:28:03.000+11:00
diff --git a/ports/nrf/common-hal/rtc/RTC.c b/ports/nrf/common-hal/rtc/RTC.c
@@ -42,7 +42,6 @@
 #define RTC_CLOCK_HZ (8)
 
 volatile static uint32_t rtc_offset = 0;
-int8_t rtc_calibration = 0;
 
 const nrfx_rtc_t rtc_instance = NRFX_RTC_INSTANCE(0);
 
@@ -80,14 +79,3 @@ void common_hal_rtc_set_time(timeutils_struct_time_t *tm) {
     );
     nrfx_rtc_counter_clear(&rtc_instance);
 }
-
-// A positive value speeds up the clock by removing clock cycles.
-int common_hal_rtc_get_calibration(void) {
-    return rtc_calibration;
-}
-
-void common_hal_rtc_set_calibration(int calibration) {
-    if (calibration > 127 || calibration < -127)
-        mp_raise_ValueError(translate("calibration value out of range +/-127"));
-    rtc_calibration = calibration;
-}
