Add SSD1331 RGB565 driver.

drivers/ssd1331/README.md

@@ -0,0 +1,11 @@
+# Drivers for SSD1331 (Adafruit 0.96" OLED display)
+
+There are two versions. Both are designed to be cross-platform.
+ * `ssd1331.py` Uses 8 bit rrrgggbb color.
+ * `ssd1331_16bit.py` Uses 16 bit RGB565 color.
+
+The `ssd1331_16bit` version requires 12KiB of RAM for the frame buffer, while
+the standard version needs only 6KiB. For the GUI the standard version works
+well because text and controls are normally drawn with saturated colors.
+
+The 16 bit version provides greatly improved results when rendering images.

drivers/ssd1331/ssd1331_16bit.py

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+# SSD1331.py MicroPython driver for Adafruit 0.96" OLED display
+# https://www.adafruit.com/product/684
+
+# The MIT License (MIT)
+
+# Copyright (c) 2019 Peter Hinch
+
+# Permission is hereby granted, free of charge, to any person obtaining a copy
+# of this software and associated documentation files (the "Software"), to deal
+# in the Software without restriction, including without limitation the rights
+# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+# copies of the Software, and to permit persons to whom the Software is
+# furnished to do so, subject to the following conditions:
+#
+# The above copyright notice and this permission notice shall be included in
+# all copies or substantial portions of the Software.
+#
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+# THE SOFTWARE.
+
+# Show command
+# 0x15, 0, 0x5f, 0x75, 0, 0x3f  Col 0-95 row 0-63
+
+# Initialisation command
+# 0xae        display off (sleep mode)
+# 0xa0, 0x72  16 bit RGB, horizontal RAM increment
+# 0xa1, 0x00  Startline row 0
+# 0xa2, 0x00  Vertical offset 0
+# 0xa4        Normal display
+# 0xa8, 0x3f  Set multiplex ratio
+# 0xad, 0x8e  Ext supply
+# 0xb0, 0x0b  Disable power save mode
+# 0xb1, 0x31  Phase period
+# 0xb3, 0xf0  Oscillator frequency
+# 0x8a, 0x64, 0x8b, 0x78, 0x8c, 0x64, # Precharge
+# 0xbb, 0x3a  Precharge voltge
+# 0xbe, 0x3e  COM deselect level
+# 0x87, 0x06  master current attenuation factor 
+# 0x81, 0x91  contrast for all color "A" segment
+# 0x82, 0x50  contrast for all color "B" segment 
+# 0x83, 0x7d  contrast for all color "C" segment 
+# 0xaf        Display on
+
+import framebuf
+import utime
+import gc
+
+class SSD1331(framebuf.FrameBuffer):
+    # Convert r, g, b in range 0-255 to a 16 bit colour value RGB565
+    #  acceptable to hardware: rrrrrggggggbbbbb
+    @staticmethod
+    def rgb(r, g, b):
+        return ((r & 0xf8) << 5) | ((g & 0x1c) << 11) | (b & 0xf8) | ((g & 0xe0) >> 5)
+
+    def __init__(self, spi, pincs, pindc, pinrs, height=64, width=96):
+        self.spi = spi
+        self.rate = 6660000  # Data sheet: 150ns min clock period
+        self.pincs = pincs
+        self.pindc = pindc  # 1 = data 0 = cmd
+        self.height = height  # Required by Writer class
+        self.width = width
+        # Save color mode for use by writer_gui (blit)
+        self.mode = framebuf.RGB565
+        gc.collect()
+        self.buffer = bytearray(self.height * self.width * 2)
+        super().__init__(self.buffer, self.width, self.height, self.mode)
+        pinrs(0)  # Pulse the reset line
+        utime.sleep_ms(1)
+        pinrs(1)
+        utime.sleep_ms(1)
+        self._write(b'\xae\xa0\x72\xa1\x00\xa2\x00\xa4\xa8\x3f\xad\x8e\xb0'\
+        b'\x0b\xb1\x31\xb3\xf0\x8a\x64\x8b\x78\x8c\x64\xbb\x3a\xbe\x3e\x87'\
+        b'\x06\x81\x91\x82\x50\x83\x7d\xaf', 0)
+        gc.collect()
+        self.show()
+
+    def _write(self, buf, dc):
+        self.spi.init(baudrate=self.rate, polarity=1, phase=1)
+        self.pincs(1)
+        self.pindc(dc)
+        self.pincs(0)
+        self.spi.write(buf)
+        self.pincs(1)
+
+    def show(self, _cmd=b'\x15\x00\x5f\x75\x00\x3f'):  # Pre-allocate
+        self._write(_cmd, 0)
+        self._write(self.buffer, 1)

drivers/ssd1331/test_colors.py

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+# test_colors.py Test color rendition on SSD1331 (Adafruit 0.96" OLED).
+# Author Peter Hinch
+# Released under the MIT licence.
+
+import machine
+# Can test either driver
+# from ssd1331 import SSD1331 as SSD
+from ssd1331_16bit import SSD1331 as SSD
+
+# Initialise hardware
+def setup():
+    pdc = machine.Pin('X1', machine.Pin.OUT_PP, value=0)
+    pcs = machine.Pin('X2', machine.Pin.OUT_PP, value=1)
+    prst = machine.Pin('X3', machine.Pin.OUT_PP, value=1)
+    spi = machine.SPI(1)
+    ssd = SSD(spi, pcs, pdc, prst)  # Create a display instance
+    return ssd
+
+ssd = setup()
+ssd.fill(0)
+# Operate in landscape mode
+x = 0
+for y in range(96):
+    ssd.line(y, x, y, x+20, ssd.rgb(round(255*y/96), 0, 0))
+x += 20
+for y in range(96):
+    ssd.line(y, x, y, x+20, ssd.rgb(0, round(255*y/96), 0))
+x += 20
+for y in range(96):
+    ssd.line(y, x, y, x+20, ssd.rgb(0, 0, round(255*y/96)))
+ssd.show()

drivers/ssd1351/ssd1351_16bit.py

@@ -9,7 +9,7 @@
 
 # The MIT License (MIT)
 
-# Copyright (c) 2018 Peter Hinch
+# Copyright (c) 2019 Peter Hinch
 
 # Permission is hereby granted, free of charge, to any person obtaining a copy
 # of this software and associated documentation files (the "Software"), to deal

drivers/ssd1351/test_colors_96.py

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+# test_colors_96.py
+# Check color mapping. Runs on 96 row display (change height for 128 row)
+
+import machine
+from ssd1351_16bit import SSD1351 as SSD
+
+# Initialise hardware
+def setup():
+    pdc = machine.Pin('X1', machine.Pin.OUT_PP, value=0)
+    pcs = machine.Pin('X2', machine.Pin.OUT_PP, value=1)
+    prst = machine.Pin('X3', machine.Pin.OUT_PP, value=1)
+    spi = machine.SPI(1)
+    ssd = SSD(spi, pcs, pdc, prst, height=96)  # Create a display instance
+    return ssd
+
+ssd = setup()
+ssd.fill(0)
+x = 0
+for y in range(128):
+    ssd.line(y, x, y, x+20, ssd.rgb(round(255*y/128), 0, 0))
+x += 20
+for y in range(128):
+    ssd.line(y, x, y, x+20, ssd.rgb(0, round(255*y/128), 0))
+x += 20
+for y in range(128):
+    ssd.line(y, x, y, x+20, ssd.rgb(0, 0, round(255*y/128)))
+ssd.show()