Add SD card demo

demo_sdcard.py

@@ -0,0 +1,104 @@
+"""ILI9341 demo (SD Card with touchscreen demo).
+
+The Micropython Machine SDCard library can cause conflicts with the ILI9341.
+Therefore, I'm using micropython-lib sdcard.py to control the SD Card.
+https://github.com/micropython/micropython-lib/tree/master/micropython/drivers/storage/sdcard
+
+The SD Card should be set to the same SPI bus as the touchscreen because they
+both run at slower speeds.  The display should be run on it's own SPI bus to
+take advantage of the higher bandwidth.
+
+If your board has a built-in SD card then you will want to identify what GPIO
+pins and what SPI bus it uses.  This demo was tested using a Lolin 32 Pro
+which uses bus 1 (HSPI) for the SD card and GPIO pin 13 for CS.  Therefore,
+the SD Card and the touch screen will share HSPI and the display will be on
+VSPI.
+
+Demo requires the Python41x49.raw image to be copied to the  SD card.  The
+SD card should be formatted to Fat32.
+"""
+from ili9341 import Display, color565
+from xpt2046 import Touch
+from machine import idle, Pin, SPI  # type: ignore
+from sdcard import SDCard
+import os
+
+
+class Demo(object):
+    """SD Card with touchscreen demo."""
+    CYAN = color565(0, 255, 255)
+    PURPLE = color565(255, 0, 255)
+    WHITE = color565(255, 255, 255)
+
+    def __init__(self, display, spi2):
+        """Initialize box.
+
+        Args:
+            display (ILI9341): display object
+            spi2 (SPI): SPI bus
+        Notes:
+            Some ILI9341's require touchscreen width & height to be swapped
+            when the Touch class is initialized.
+        """
+        self.display = display
+        self.touch = Touch(spi2, cs=Pin(5), int_pin=Pin(0),
+                           int_handler=self.touchscreen_press,
+                           width=240, height=320)
+        # Display initial message
+        self.display.draw_text8x8(self.display.width // 2 - 32,
+                                  self.display.height - 9,
+                                  "TOUCH ME",
+                                  self.WHITE,
+                                  background=self.PURPLE)
+
+    def touchscreen_press(self, x, y):
+        """Process touchscreen press events."""
+        # x, y = y, x  # Some screens require swapping X and Y
+        # x = (self.display.width - 1) - x  # Some screens require flipping X
+        y = (self.display.height - 1) - y  # Some screens require flipping Y
+
+        # Display coordinates
+        self.display.draw_text8x8(self.display.width // 2 - 32,
+                                  self.display.height - 9,
+                                  "{0:03d}, {1:03d}".format(x, y),
+                                  self.CYAN)
+
+        # Draw image from SD Card
+        try:
+            x -= 20  # Image center X
+            y -= 25  # Image center Y
+            x = max(x, 41)
+            x = min(x, self.display.width - 42)
+            y = max(y, 49)
+            y = min(y, self.display.height - 50)
+            self.display.draw_image('sd/Python41x49.raw', x, y, 41, 49)
+        except OSError as e:
+            print("Error:", e)
+
+
+def test():
+    """Test code."""
+    # Initialize SPI bus for touch screen & built-in SD card (bus must match).
+    spi1 = SPI(1, baudrate=1000000, sck=Pin(14), mosi=Pin(15), miso=Pin(2))
+    # Initialize and mount SD card
+    sd_cs = Pin(13)  # When using an internal SD card, ensure CS matches.
+    sd = SDCard(spi1, sd_cs)
+    os.mount(sd, '/sd')
+    # Initialize SPI bus for display
+    spi2 = SPI(2, baudrate=40000000, sck=Pin(18), mosi=Pin(23), miso=Pin(19))
+    display = Display(spi2, dc=Pin(22), cs=Pin(19), rst=Pin(21))
+
+    Demo(display, spi1)
+
+    try:
+        while True:
+            idle()
+
+    except KeyboardInterrupt:
+        print("\nCtrl-C pressed.  Cleaning up and exiting...")
+    finally:
+        display.cleanup()  # Clean up display
+        os.umount('/sd')  # Unmount SD card
+
+
+test()