Prior to Damiens low power fix for D series

Author: peterhinch

lowpower/README.md

@@ -1,10 +1,12 @@
 # A low power usayncio adaptation
 
-Release 0.11 9th April 2019
+Release 0.11 11th April 2019
 
-API change: low power applications must now import `rtc_time_cfg` and set its
+API changes: low power applications must now import `rtc_time_cfg` and set its
 `enabled` flag.  
-This is specific to Pyboards including the D series.
+`Latency` class: Constructor requires event loop arg.  
+
+This module is specific to Pyboards including the D series.
 
  1. [Introduction](./README.md#1-introduction)  
  2. [Installation](./README.md#2-installation)  
@@ -252,10 +254,10 @@ Horizontal 500μs/div
 
 ### 3.2.4 Pyboard D measurements
 
-As of this release the two demo applications consume around 3.3mA. This is high
-because the unused pins are floating. When I discover which pins can be set to
-input with pullups as per the Pyboard 1.x implementation I hope to see figures
-comparable to Pyboard 1.x.
+As of this release the `lpdemo.py` script consumes around 1.1mA. I believe this
+can be reduced because some unused pins are floating. When I discover which
+pins can be set to input with pullups as per the Pyboard 1.x implementation I
+hope to see figures comparable to Pyboard 1.x.
 
 ###### [Contents](./README.md#a-low-power-usayncio-adaptation)
 
@@ -283,12 +285,12 @@ reason is explained in the code comments. It is recommended to use the `utime`
 method explicitly if needed.
 
 Latency Class:  
- * Constructor: Positional arg `t_ms=100`. Period for which the scheduler
- enters `stop` i.e. initial latency period.
- * Method: `value` Arg `val=None`. Controls period for which scheduler stops.
- It returns the period in ms. If the default `None` is passed the value is
- unchanged. If 0 is passed the scheduler runs at full speed. A value > 0 sets
- the stop period in ms.
+ * Constructor: Positional args `loop` - the event loop, `t_ms=100` - period
+ for which the scheduler  enters `stop` i.e. initial latency period.
+ * Method: `value` Arg `val=None`. Controls period for which scheduler
+ stops. It returns the period in ms prior to any change in value. If the
+ default `None` is passed the value is unchanged. If 0 is passed the scheduler
+ runs at full speed. A value > 0 sets the stop period in ms.
 
 The higher the value, the greater the latency experienced by other tasks and
 by I/O. Smaller values will result in higher power consumption with other tasks
@@ -298,7 +300,7 @@ The class is a singleton consequently there is no need to pass an instance
 around or to make it global. Once instantiated, latency may be changed by
 
 ```python
-rtc_time.Latency().value(t)
+rtc_time.Latency(t)
 ```
 
 ###### [Contents](./README.md#a-low-power-usayncio-adaptation)

lowpower/rtc_time.py

@@ -14,12 +14,12 @@
 from os import uname
 from rtc_time_cfg import enabled
 if not enabled:
-    print('rtc_time module has not been enabled.')
-    sys.exit(0)
+    raise ImportError('rtc_time is not enabled.')
+
+# sleep_ms is defined to stop things breaking if someone imports uasyncio.core
+# Power won't be saved if this is done.
+sleep_ms = utime.sleep_ms
 
-_PERIOD = const(604800000)  # ms in 7 days
-_PERIOD_2 = const(302400000)  # half period
-_SS_TO_MS = 1000/256  # Subsecs to ms
 d_series = uname().machine[:5] == 'PYBD_'
 use_utime = True  # Assume the normal utime timebase
 
@@ -39,25 +39,37 @@
     raise OSError('rtc_time.py is Pyboard-specific.')
 
 # For lowest power consumption set unused pins as inputs with pullups.
-# Note the 4K7 I2C pullups on X9 X10 Y9 Y10.
+# Note the 4K7 I2C pullups on X9 X10 Y9 Y10 (Pyboard 1.x).
 if d_series:
     print('Running on Pyboard D')  # Investigate which pins we can do this to TODO
-    #for pin in [p for p in dir(pyb.Pin.board) if p[0] in 'XYW']:
-        #pin_x = pyb.Pin(pin, pyb.Pin.IN, pyb.Pin.PULL_UP)
+#    pinlist = [p for p in dir(pyb.Pin.board) if p.startswith('W') and p[1].isdigit() and p[-1].isdigit()]
+#    sorted(pinlist, key=lambda s: int(s[1:]))
+    #pinlist = ['W3', 'W5', 'W6', 'W7', 'W8', 'W9', 'W10', 'W11', 'W12', 'W14', 'W15',
+            #'W16', 'W17', 'W18', 'W19', 'W20', 'W22', 'W23', 'W24', 'W25',
+            #'W26', 'W27', 'W28', 'W29', 'W30', 'W32', 'W33', 'W34', 'W43', 'W45',
+            #'W46', 'W47', 'W49', 'W50', 'W51', 'W52', 'W53', 'W54', 'W55', 'W56',
+            #'W57', 'W58', 'W59', 'W60', 'W61', 'W62', 'W63', 'W64', 'W65', 'W66',
+            #'W67', 'W68', 'W70', 'W71', 'W72', 'W73', 'W74']
+    # sorted([p for p in dir(pyb.Pin.board) if p[0] in 'XY' and p[-1].isdigit()], key=lambda x: int(x[1:]) if x[0]=='X' else int(x[1:])+100)
+    pinlist = ['X1', 'X2', 'X3', 'X4', 'X5', 'X6', 'X7', 'X8', 'X9', 'X10', 'X11', 'X12',
+                'Y3', 'Y4', 'Y5', 'Y6', 'Y7', 'Y8', 'Y9', 'Y10', 'Y11', 'Y12']
+    for pin in pinlist:
+        pin_x = pyb.Pin(pin, pyb.Pin.IN, pyb.Pin.PULL_UP)
+    pyb.Pin('EN_3V3').off()
 else:
     print('Running on Pyboard 1.x')
     for pin in [p for p in dir(pyb.Pin.board) if p[0] in 'XY']:
         pin_x = pyb.Pin(pin, pyb.Pin.IN, pyb.Pin.PULL_UP)
 # User code redefines any pins in use
 
-# sleep_ms is defined to stop things breaking if someone imports uasyncio.core
-# Power won't be saved if this is done.
-sleep_ms = utime.sleep_ms
-if use_utime:  # Run utime: Pyboard connected to PC via USB or alien platform
+if use_utime:
     ticks_ms = utime.ticks_ms
     ticks_add = utime.ticks_add
     ticks_diff = utime.ticks_diff
-else:
+else:   # All conditions met for low power operation
+    _PERIOD = const(604800000)  # ms in 7 days
+    _PERIOD_2 = const(302400000)  # half period
+    _SS_TO_MS = 1000/256  # Subsecs to ms
     rtc = pyb.RTC()
     # dt: (year, month, day, weekday, hours, minutes, seconds, subseconds)
     # weekday is 1-7 for Monday through Sunday.
@@ -82,9 +94,6 @@ def ticks_diff(end, start):
 
 import uasyncio as asyncio
 
-# Common version has a needless dict: https://www.python.org/dev/peps/pep-0318/#examples
-# https://stackoverflow.com/questions/6760685/creating-a-singleton-in-python
-# Resolved: https://forum.micropython.org/viewtopic.php?f=2&t=5033&p=28824#p28824
 def singleton(cls):
     instance = None
     def getinstance(*args, **kwargs):
@@ -124,6 +133,7 @@ def _run(self):
                     rtc.wakeup(None)
 
     def value(self, val=None):
-        if val is not None and not use_utime:
+        v = self._t_ms
+        if val is not None:
             self._t_ms = max(val, 0)
-        return self._t_ms
+        return v