feat(lis2mdl): Add OLED digital compass example.

lib/lis2mdl/README.md

@@ -213,6 +213,7 @@ print("Register dump:", regs)
 | `power_on()` / `power_off()`      | Power management               |
 | `soft_reset()` / `reboot()`        | Sensor reset functions         |
 
+
 ---
 
 ## Examples
@@ -229,6 +230,7 @@ print("Register dump:", regs)
 | low_power_one_shot.py       | Energy-efficient sampling example. Uses `power_off()` between readings and `read_one_shot()` every 10 seconds, then prints values and free memory. |
 | magnet_compass.py           | Flat compass example that computes heading and cardinal direction from the LIS2MDL magnetic field. Useful for basic orientation demos. |
 | magnet_fieldForce.py        | Magnetic field magnitude example that shows total field strength in microtesla. Useful for observing magnetic disturbances and relative field changes. |
+| compass_display.py | Graphical compass with OLED display. **Dependency: `steami_screen` driver/module required (`Screen`, `SSD1327Display`).** |
 
 ---
 

lib/lis2mdl/examples/compass_display.py

@@ -0,0 +1,68 @@
+"""Digital compass example using LIS2MDL and Steami Screen OLED widget.
+
+Reads the magnetic heading using the built-in flat heading method,
+and draws a dynamic compass on the display using the Screen widget.
+Includes a preliminary 3D calibration step.
+"""
+
+from time import sleep_ms
+
+import ssd1327
+from lis2mdl import LIS2MDL
+from machine import I2C, SPI, Pin
+from steami_screen import Screen, SSD1327Display
+
+# Layout Constants for Calibration Screen
+CALIB_MSG1_X = 12
+CALIB_MSG1_Y = 50
+CALIB_MSG2_X = 4
+CALIB_MSG2_Y = 70
+
+# Hardware Initialization
+i2c = I2C(1)
+mag = LIS2MDL(i2c)
+
+spi = SPI(1)
+dc = Pin("DATA_COMMAND_DISPLAY")
+res = Pin("RST_DISPLAY")
+cs = Pin("CS_DISPLAY")
+
+# Initialize the raw display, then wrap it in the high-level Screen widget system
+raw_display = ssd1327.WS_OLED_128X128_SPI(spi, dc, res, cs)
+display = SSD1327Display(raw_display)
+screen = Screen(display)
+
+try:
+    # Calibration Phase
+    raw_display.fill(0)
+    raw_display.text("Calibrating...", CALIB_MSG1_X, CALIB_MSG1_Y, 15)
+    raw_display.text("Move in 8-shape", CALIB_MSG2_X, CALIB_MSG2_Y, 15)
+    raw_display.show()
+    sleep_ms(100)
+
+    print("Calibrate the magnetometer by moving it in a figure-eight pattern.")
+    mag.calibrate_minmax_3d()
+    print("Calibration complete.")
+
+    # Main Compass Loop
+    while True:
+        heading_deg = mag.heading_flat_only()
+        direction = mag.direction_label(heading_deg)
+
+        # Drawing Phase (Delegated entirely to the steami_screen widget)
+        screen.clear()
+        screen.compass(heading_deg)
+        screen.show()
+
+        print("Angle: {:3.0f}° | Direction: {}".format(heading_deg, direction))
+
+        sleep_ms(50)
+
+except KeyboardInterrupt:
+    pass
+finally:
+    # Clean up and power off display on exit
+    screen.clear()
+    screen.show()
+    sleep_ms(100)
+    raw_display.power_off()