feat(steami_screen): add example of compass

Author: Charly-sketch

lib/steami_screen/examples/compass_demo.py

@@ -0,0 +1,42 @@
+"""
+Displays a compass with a rotating needle based on the LIS2MDL magnetometer.
+"""
+
+from time import sleep_ms
+
+import ssd1327
+from lis2mdl import LIS2MDL
+from machine import I2C, SPI, Pin
+from steami_screen import Screen, SSD1327Display
+
+# --- Screen setup ---
+spi = SPI(1)
+dc = Pin("DATA_COMMAND_DISPLAY")
+res = Pin("RST_DISPLAY")
+cs = Pin("CS_DISPLAY")
+
+raw_display = ssd1327.WS_OLED_128X128_SPI(spi, dc, res, cs)
+display = SSD1327Display(raw_display)
+screen = Screen(display)
+
+# --- Sensor setup ---
+i2c = I2C(1)
+sensor = LIS2MDL(i2c)
+
+print("Calibrate the magnetometer by moving it flat.")
+sensor.calibrate_minmax_2d()
+print("Calibration complete.")
+
+heading = 0
+
+# --- Main loop ---
+while True:
+    angle = sensor.heading_flat_only()
+
+    screen.clear()
+    screen.compass(angle)
+    screen.show()
+
+    print("Cap:", angle, "°")
+
+    sleep_ms(50)