simulator: Reverse the simulated PPG waveform

This avoids an implusive change in base value and makes the waveform a
little more interesting.

Signed-off-by: Daniel Thompson <daniel@redfelineninja.org.uk>

1 files changed, 10 insertions, 4 deletions

diff --git a/wasp/boards/simulator/watch.py b/wasp/boards/simulator/watch.py
index 9f9920c..abdf571 100644
--- a/wasp/boards/simulator/watch.py
+++ b/wasp/boards/simulator/watch.py
@@ -140,11 +140,11 @@ class HRS():
 9186,9182,9182,9193,9193,9193,9197,9197,9188,9204,9204,9212,9212,9212,9223,9223,
 9228,9228,9228,9235,9235,9215,9215,9215,9217,9217,9225,9225,9225,9230,9230,9237,
 9237,9237,9246,9246,9260,9260,9260,9270,9270,9269,9269,9269,9256,9256,9256,9256,
-9256,9263,9263,9274,9274,9274,9288,9288,9292,9292,9292,9307,9307,9310,9310,9310,
-9292,9292,9291,9291,9291,9297,9297,9298,9298,9298
+9256,9263,9263,9274,9274,9274,9288,9288,9292,9292,9292,9307,9307,9310
 )
     def __init__(self):
         self._i = 0
+        self._step = 1
 
     def enable(self):
         pass
@@ -154,9 +154,15 @@ class HRS():
 
     def read_hrs(self):
         d = self.DATA[self._i]
-        self._i += 1
+
+        self._i += self._step
         if self._i >= len(self.DATA):
-            self._i = 0
+            self._i -= 1
+            self._step = -1
+        elif self._i < 0:
+            self._i += 1
+            self._step = 1
+
         return d
 
 backlight = Backlight()