Add solution to blink exercise

Author: bessman

pslab/blink.py

@@ -0,0 +1,56 @@
+"""FOSSASIA Summit 2025 - PSLab Development 101 exercises."""
+
+import time
+
+import pslab
+import pslab.protocol as CP
+
+
+def blink(psl: pslab.ScienceLab, color: tuple[int, int, int], period: int) -> None:
+    """Blink the onbard RGB LED.
+
+    Parameters
+    ----------
+    psl : pslab.ScienceLab
+    color : tuple[int, int, int]
+        Green, red, blue, each in range 0-255.
+    period : int
+        Blink period in milliseconds.
+    """
+    toggle = time.time()
+    state = 0
+
+    while True:
+        if period / 2 < (time.time() - toggle) * 1000:
+            if state:
+                # Turn off LED.
+                psl.rgb_led((0, 0, 0))
+            else:
+                # Turn on LED.
+                psl.rgb_led(color)
+
+            state = not state
+            toggle = time.time()
+
+
+def blink_c(psl: pslab.ScienceLab, color: tuple[int, int, int], period: int) -> None:
+    """Blink the RGB LED using firmware implementation.
+
+    Parameters
+    ----------
+    psl : pslab.ScienceLab
+    color : tuple[int, int, int]
+        Green, red, blue, each in range 0-255.
+    period : int
+        Blink period in milliseconds.
+    """
+    if not period:
+        cmd = CP.NONSTANDARD_IO + CP.Byte.pack(11)
+        psl.device.exchange(cmd)
+        psl.rgb_led(color)
+        return
+
+    cmd = CP.NONSTANDARD_IO + CP.Byte.pack(10)
+    args = CP.ShortInt.pack(period)
+    args += bytes(color)
+    psl.device.exchange(cmd, args)