#*********************************************************************************************************************************************************
#  Title : AtSAMD51 Internal Real Time Clock tester                                                                                                      *
#                                                                                                                                                        *
#  Author : Gert van Biljon                                                                                                                              *
#                                                                                                                                                        *
#  EMail : gertvb@gmail.com                                                                                                                              *
#                                                                                                                                                        *
#*********************************************************************************************************************************************************

#*********************************************************************************************************************************************************
#  What am I : Small program to test:                                                                                                                    *
#              1. Setting the time on the internal real time clock of the AtSAMD51 as found on the ADAFruit Feather M4                                   *
#              2. Checking the time in the RTC after pressing RESET on the Feather M4                                                                    *
#                                                                                                                                                        *
#  Why : After updating CircuitPython from 5.3.1 to 6.2.0, I've found that upon pressing the RESET button the values in the internal RTC are all now     *
#        discarded or rather set to 2000/1/1 . .                                                                                                         *
#                                                                                                                                                        *
#  Background : I am using a Feather M4 with a LiPoly battery as controller for the borehole pumps supplying drinking water to our house and farm.       *
#                                                                                                                                                        *
#               With the luxury of the Flash storage on the Feather M4, I log the times when the pumps are started and stopped, grabbing the time from   *
#               the internal RTC on the AtSAMD51                                                                                                         *
#                                                                                                                                                        *
#               What is VERY useful on CircuitPython 5.3.1 is that the internal RTC doesn't lose its time, even when the reset button on the Feather is  *
#               pressed!                                                                                                                                 *
#                                                                                                                                                        *
#               This means that you only have to set the time ONCE with :                                                                                *
#                   my_real_time_clock.datetime = time.struct_time((2021, 03, 16, 07, 43, 2, 0, -1, -1))                                                 *
#               and thereafter the Feather keeps the time as long as the LiPoly is connected and full, and the above code can be commented out           *
#                                                                                                                                                        *
#  Hardware : ADAFruit Feather M4 Express, (Atmel AtSAMD51 ARM M4)                                                                                       *
#             LiPoly battery                                                                                                                             *
#*********************************************************************************************************************************************************

#*********************************************************************************************************************************************************
#  History : 2021/04/08 : Updated CircuitPython from 5.3.1 to 6.2.0 and found that the time values stored in the RTC are now discarded when pressing     *
#                         RESET                                                                                                                          *
#                         Created this as sample for filing the issue to GitHub                                                                          *
#*********************************************************************************************************************************************************

#*********************************************************************************************************************************************************
# $Author:: Gert_v_B                                                                                                                                   $ *
# $Date:: 2021-04-08 09:23:19 +0200 (Thu, 08 Apr 2021)                                                                                                 $ *
# $Id:: code.py 1395 2021-04-08 07:23:19Z Gert_v_B                                                                                                     $ *
# $Header:: https://techexplorer/svn/SVN_Repository/python/circuitpython_rtc_persistency_test/code.py 1395 2021-04-08 07:23:19Z Gert_v_B               $ *
#*********************************************************************************************************************************************************

import rtc
import time
import supervisor

my_real_time_clock = rtc.RTC() #Uses Internal ADC on AtSAMD51

#To set the time one has to run this script with the following line uncommented.
#With the Lipoly battery connected to the Feather, the internal RTC keeps correct time, even when pressing the reset button
#This should only be needed to run once in the lifetime of the project
#my_real_time_clock.datetime = time.struct_time((2021, 04, 08, 08, 54, 05, 0, -1, -1))

while True:
    current_time = my_real_time_clock.datetime
    my_datestring = "{:2d}".format(current_time.tm_year) + "/{:02d}".format(current_time.tm_mon) + "/{:02d}".format(current_time.tm_mday)
    my_timestring = "{:02d}".format(current_time.tm_hour) +  ":{:02d}".format(current_time.tm_min) +     ":{:02d}".format(current_time.tm_sec)

    if supervisor.runtime.serial_connected:
        print ("Time : ", my_datestring, " ", my_timestring, "\n", sep = "")

    time.sleep(1)
#while True: