DS3231: Update README. Modify test for Pyboard D.

DS3231/README.md

@@ -28,10 +28,6 @@ local time (`utime.localtime()`) is based on the RTC time. Changes to local
 time don't propagate to the RTC which must explicitly be set. This holds for
 the Pyboard, ESP8266 and ESP32.
 
-The official ESP32 port currently lacks support for the RTC so the Loboris port
-should be used for this purpose. The driver supports both but if the official
-port is used only the local time can be updated from the DS3231.
-
 ## 1.1 The DS3231 class
 
 Constructor:  

DS3231/ds3231_port_test.py

@@ -7,8 +7,13 @@
 from machine import Pin, I2C
 import utime
 import sys
+import uos
 from ds3231_port import DS3231
 
+# If powering the DS3231 from a Pyboard D 3V3 output:
+if uos.uname().machine.split(' ')[0][:4] == 'PYBD':
+    Pin.board.EN_3V3.value(1)
+
 # A Pyboard test
 #from pyb import RTC
 #rtc = RTC()