scripts: add nxp_rgb_count.py

scripts/nxp_rgb_count.py

@@ -0,0 +1,28 @@
+#!/usr/bin/env python3
+import sys
+
+# Reads an NXP (single colour) frame from stdin and returns the index of the first led that's fully on
+# Args are indices to ignore (for buttons that can not be turned off)
+ignore = set([int(x) for x in sys.argv[1:]])
+cmdi = 0
+leds = []
+while cmdi < 3:
+    expected = f"7f 0{cmdi + 1} "
+    cmd = input().lower().strip()
+    if not cmd.startswith(expected):
+        print("Try again. Expecting " + expected)
+        continue
+
+    cmdi += 1
+
+    cmdl = cmd.split(" ")
+    leds += cmdl[4:]
+
+for i in range(len(leds)):
+    if len(leds[i]) != 2:
+        print(f"Invalid data at {i}")
+    elif leds[i] == "ff":
+        if i in ignore:
+            continue
+        print(f"LED found at {i} {hex(i)}")
+        break