Fix some comments.

Signed-off-by: Keith Rothman <537074+litghost@users.noreply.github.com>

prjxray/math_models.py

@@ -0,0 +1,65 @@
+""" Math models are used to represent abstract operations for the timing models.
+This is useful for creating excel workbooks that can update dynamically, or
+generating a model with symbolic constants to be backsolved.
+"""
+
+
+class ExcelMathModel(object):
+    """ Math model used for outputting to an dyanmic Excel sheet. """
+
+    def __init__(self):
+        pass
+
+    def sum(self, elems):
+        sum_val = '(' + ' + '.join(elems) + ')'
+        if sum_val == '()':
+            return '0'
+        else:
+            return sum_val
+
+    def product(self, elems):
+        sum_val = '(' + ' * '.join(elems) + ')'
+        if sum_val == '()':
+            return '1'
+        else:
+            return sum_val
+
+    def plus(self, a, b):
+        return self.sum((a, b))
+
+    def divide(self, a, b):
+        return '({}/{})'.format(a, b)
+
+    def multiply(self, a, b):
+        return '({}*{})'.format(a, b)
+
+    def eval(self, elem):
+        return '=' + elem
+
+
+def PythonMathModel(object):
+    """ Math model used for outputting values equalated immediately. """
+
+    def __init__(self):
+        pass
+
+    def sum(self, elems):
+        return sum(elems)
+
+    def product(self, elems):
+        v = 1.0
+        for elem in elems:
+            v *= elem
+        return v
+
+    def divide(self, a, b):
+        return a / b
+
+    def plus(self, a, b):
+        return a + b
+
+    def multiply(self, a, b):
+        return a * b
+
+    def eval(self, elem):
+        return elem

prjxray/tile.py

@@ -8,7 +8,7 @@ TileDbs = namedtuple(
     'TileDbs', 'segbits block_ram_segbits ppips mask tile_type')
 
 
-class OutpinTiming(namedtuple('OutpinTiming', 'delays drive_resistance')):
+class OutPinTiming(namedtuple('OutPinTiming', 'delays drive_resistance')):
     """ Timing for site output pins.
 
     Attributes
@@ -22,7 +22,7 @@ class OutpinTiming(namedtuple('OutpinTiming', 'delays drive_resistance')):
     pass
 
 
-class InpinTiming(namedtuple('InpinTiming', 'delays capacitance')):
+class InPinTiming(namedtuple('InPinTiming', 'delays capacitance')):
     """ Timing for site input pins.
 
     Attributes
@@ -125,7 +125,7 @@ class SitePin(namedtuple('SitePin', 'name wire timing')):
         all sites of the same type.
     wire : str
         Wire name within the tile.  This name is site instance specific.
-    timing : Either InpinTiming or OutpinTiming
+    timing : Either InPinTiming or OutPinTiming
         Timing of site pin. May be None if database lacks timing information.
 
     """
@@ -177,13 +177,13 @@ def get_pip_timing(pip_timing_json):
 
 
 def get_site_pin_timing(site_pin_info):
-    """ Convert site_pin_info JSON into InpinTiming or OutpinTiming object.
+    """ Convert site_pin_info JSON into InPinTiming or OutPinTiming object.
 
     Returns
     -------
     If timing information is not present for this site pin, returns None.
-    If this is an output pin, returns OutpinTiming.
-    If this is an input pin, returns InpinTiming.
+    If this is an output pin, returns OutPinTiming.
+    If this is an input pin, returns InPinTiming.
 
     """
     if isinstance(site_pin_info, str):
@@ -198,13 +198,13 @@ def get_site_pin_timing(site_pin_info):
 
     if 'cap' in site_pin_info:
         assert 'res' not in site_pin_info
-        return wire, InpinTiming(
+        return wire, InPinTiming(
             delays=delays,
             capacitance=float(site_pin_info['cap']) / CAPACITANCE_FACTOR,
         )
     else:
         assert 'res' in site_pin_info
-        return wire, OutpinTiming(
+        return wire, OutPinTiming(
             delays=delays,
             drive_resistance=float(site_pin_info['res']) / RESISTANCE_FACTOR,
         )

prjxray/timing.py

@@ -30,31 +30,31 @@ a pi-model.
 
 Example timing tree:
 
-+------+
-|Outpin|
-+--+---+
-   |
-   |
-   v
-+--+--+
-|Wire |
-+--+--+
-   |
-   +-----------------+
-   |                 |
-+--+---+     +-------+------+
-|Buffer|     |PassTransistor|
-+--+---+     +------+-------+
-   |                |
-   v                v
-+--+-+           +--+-+
-|Wire|           |Wire|
-+--+-+           +--+-+
-   |                |
-   v                v
-+--+--+          +--+--+
-|Inpin|          |Inpin|
-+-----+          +-----+
+    +------+
+    |Outpin|
+    +--+---+
+    |
+    |
+    v
+    +--+--+
+    |Wire |
+    +--+--+
+    |
+    +-----------------+
+    |                 |
+    +--+---+     +-------+------+
+    |Buffer|     |PassTransistor|
+    +--+---+     +------+-------+
+    |                |
+    v                v
+    +--+-+           +--+-+
+    |Wire|           |Wire|
+    +--+-+           +--+-+
+    |                |
+    v                v
+    +--+--+          +--+--+
+    |Inpin|          |Inpin|
+    +-----+          +-----+
 
 Note on units:
 
@@ -160,72 +160,6 @@ def fast_slow_tuple_to_corners(arr):
     }
 
 
-# Math models are used to represent abstract operations for the timing models.
-# This is useful for creating excel workbooks that can update dynamically, or
-# generating a model with symbolic constants to be backsolved.
-
-
-class ExcelMathModel(object):
-    """ Math model used for outputting to an dyanmic Excel sheet. """
-
-    def __init__(self):
-        pass
-
-    def sum(self, elems):
-        sum_val = '(' + ' + '.join(elems) + ')'
-        if sum_val == '()':
-            return '0'
-        else:
-            return sum_val
-
-    def product(self, elems):
-        sum_val = '(' + ' * '.join(elems) + ')'
-        if sum_val == '()':
-            return '1'
-        else:
-            return sum_val
-
-    def plus(self, a, b):
-        return self.sum((a, b))
-
-    def divide(self, a, b):
-        return '({}/{})'.format(a, b)
-
-    def multiply(self, a, b):
-        return '({}*{})'.format(a, b)
-
-    def eval(self, elem):
-        return '=' + elem
-
-
-def PythonMathModel(object):
-    """ Math model used for outputting values equalated immediately. """
-
-    def __init__(self):
-        pass
-
-    def sum(self, elems):
-        return sum(elems)
-
-    def product(self, elems):
-        v = 1.0
-        for elem in elems:
-            v *= elem
-        return v
-
-    def divide(self, a, b):
-        return a / b
-
-    def plus(self, a, b):
-        return a + b
-
-    def multiply(self, a, b):
-        return a * b
-
-    def eval(self, elem):
-        return elem
-
-
 class TimingNode(object):
     """ Base class for timing node models.
     """
@@ -288,6 +222,7 @@ class DownstreamNode(TimingNode):
         math : MathModel
             Math model to use to compute delays
         """
+        pass
 
 
 class Outpin(TimingNode):