SSD1306: Fix driver color-compatibility.

DISPLAYS.md

@@ -44,12 +44,12 @@ Width and height are pixels.
 
 Monochrome OLED displays based on the SSD1306 chip are supported via the
 [official driver][3d]. Displays are available from various sources and can use
-I2C or SPI interfaces. An example is [Adafruit 938][4m]. The SSD1306 driver in
-this repo has a minor addition to enable it to support demos intended for color
-displays.
+I2C or SPI interfaces. An example is [Adafruit 938][4m]. The [SSD1306 driver][14d]
+in this repo has minor additions to support demos intended for color displays.
 
 Monochrome OLED displays based on the SH1106 chip are supported via the
-[unofficial driver](https://github.com/robert-hh/SH1106).
+[unofficial driver](https://github.com/robert-hh/SH1106). The [SH1106 driver][13d]
+in this repo has minor additions to support demos intended for color displays.
 Displays are available from various sources and can use I2C or SPI interfaces.
 An exmaple is the [Inland IIC SPI 1.3" 128x64 OLED V2.0](https://www.microcenter.com/product/643965/inland-iic-spi-13-128x64-oled-v20-graphic-display-module-for-arduino-uno-r3)
 AKA [KeyStudio](https://wiki.keyestudio.com/Ks0056_keyestudio_1.3%22_128x64_OLED_Graphic_Display).
@@ -103,6 +103,8 @@ simple. See [this doc](./DRIVERS.md#7-writing-device-drivers) for details.
 [10d]: https://github.com/peterhinch/micropython-nano-gui/blob/master/DRIVERS.md#53-waveshare-400x300-pi-pico-display
 [11d]: https://github.com/peterhinch/micropython-nano-gui/blob/master/DRIVERS.md#23-drivers-for-ssd1327
 [12d]: https://github.com/peterhinch/micropython-nano-gui/blob/master/DRIVERS.md#34-driver-for-ili9486
+[13d]: https://github.com/peterhinch/micropython-nano-gui/blob/master/drivers/sh1106/sh1106.py
+[14d]: https://github.com/peterhinch/micropython-nano-gui/blob/master/drivers/ssd1306/ssd1306.py
 
 [1m]: https://www.adafruit.com/product/684
 [2m]: https://www.adafruit.com/product/1673

README.md

@@ -113,7 +113,7 @@ my GUI's employ the American spelling of `color`.
 
 ## 1.1 Change log
 
-12 Feb 2023 Add support for sh1106 driver.  
+12 Feb 2023 Add support for sh1106 driver. Fix color compatibility of SSD1306.  
 5 Sep 2022 Add support for additional Pico displays.  
 8 Aug 2022 Typo and grammar fixes from @bfiics.  
 10 May 2022 Support Waveshare Pi Pico displays.  

drivers/ssd1306/ssd1306.py

@@ -2,7 +2,7 @@
 
 from micropython import const
 import framebuf
-
+from drivers.boolpalette import BoolPalette
 
 # register definitions
 SET_CONTRAST = const(0x81)
@@ -27,7 +27,7 @@ SET_CHARGE_PUMP = const(0x8D)
 # http://docs.micropython.org/en/latest/pyboard/library/framebuf.html
 class SSD1306(framebuf.FrameBuffer):
     @staticmethod
-    def rgb(r, g, b):
+    def rgb(r, g, b):  # Color compatibility
         return int((r > 127) or (g > 127) or (b > 127))
 
     def __init__(self, width, height, external_vcc):
@@ -36,7 +36,9 @@ class SSD1306(framebuf.FrameBuffer):
         self.external_vcc = external_vcc
         self.pages = self.height // 8
         self.buffer = bytearray(self.pages * self.width)
-        super().__init__(self.buffer, self.width, self.height, framebuf.MONO_VLSB)
+        mode = framebuf.MONO_VLSB
+        self.palette = BoolPalette(mode)  # Ensure color compatibility
+        super().__init__(self.buffer, self.width, self.height, mode)
         self.init_display()
 
     def init_display(self):