Fix 96x16 OLED panel offset (#368)

* Fix 96x16 OLED panel offset. (Fixes #367.)

* Fix 96x16 tests to match _colstart=0 for these displays.

* Adds @gsmecher to contributors list.

---------

Co-authored-by: Richard Hull <rm_hull@yahoo.co.uk>

CONTRIBUTING.rst

@@ -32,4 +32,4 @@ Contributors
 * Dhrone (@dhrone)
 * George Harker (@georgeharker)
 * @Pako2
-
+* Graeme Smecher (@gsmecher)

luma/oled/device/__init__.py

@@ -241,11 +241,11 @@ def __init__(self, serial_interface=None, width=128, height=64, rotate=0, **kwar
 
         # Supported modes
         settings = {
-            (128, 64): dict(multiplex=0x3F, displayclockdiv=0x80, compins=0x12),
-            (128, 32): dict(multiplex=0x1F, displayclockdiv=0x80, compins=0x02),
-            (96, 16): dict(multiplex=0x0F, displayclockdiv=0x60, compins=0x02),
-            (64, 48): dict(multiplex=0x2F, displayclockdiv=0x80, compins=0x12),
-            (64, 32): dict(multiplex=0x1F, displayclockdiv=0x80, compins=0x12)
+            (128, 64): dict(multiplex=0x3F, displayclockdiv=0x80, compins=0x12, colstart=0),
+            (128, 32): dict(multiplex=0x1F, displayclockdiv=0x80, compins=0x02, colstart=0),
+            (96, 16): dict(multiplex=0x0F, displayclockdiv=0x60, compins=0x02, colstart=0),
+            (64, 48): dict(multiplex=0x2F, displayclockdiv=0x80, compins=0x12, colstart=32),
+            (64, 32): dict(multiplex=0x1F, displayclockdiv=0x80, compins=0x12, colstart=32)
         }.get((width, height))
 
         if settings is None:
@@ -255,7 +255,7 @@ def __init__(self, serial_interface=None, width=128, height=64, rotate=0, **kwar
         self._pages = height // 8
         self._mask = [1 << (i // width) % 8 for i in range(width * height)]
         self._offsets = [(width * (i // (width * 8))) + (i % width) for i in range(width * height)]
-        self._colstart = (0x80 - self._w) // 2
+        self._colstart = settings['colstart']
         self._colend = self._colstart + self._w
 
         self.command(

tests/test_ssd1306.py

@@ -65,7 +65,7 @@ def test_init_96x16():
         # set contrast
         call(129, 207),
         # reset the display
-        call(33, 16, 111, 34, 0, 1),
+        call(33, 0, 95, 34, 0, 1),
         # called last, is a command to show the screen
         call(175)
     ])