-static unsigned char user_params[MAX_USER_PARAMS] = { 0, 0, 0 };
-static unsigned char user_params_max[MAX_USER_PARAMS] = { 3, 2, 2 };
+/*
+ * How does the user_params setup mode work:
+ *
+ * There is an array of user-settable parameters user_params[N_USER_PARAMS],
+ * each of which has its own maximum value (user_params_max[N_USER_PARAMS].
+ * These parameters can be modified in the following way:
+ *
+ * Long press of button 1 enters the setup mode.
+ * In the setup mode, status and illumination LEDs both blink in inversion
+ * number mode.
+ * The # of blinks of the illumination LED shows which user_param is
+ * being modified now,
+ * and the # of blinks of the status LED shows the value of this particular
+ * user_param.
+ *
+ * Long press of button 1 selects the next user_param,
+ * short press of button 0 decrements this particular user_param value,
+ * short press of button 1 increments this particular user_param value.
+ *
+ * If USER_PARAMS_WRAPPING is #defined, decrementing the zero leads to
+ * the maximum value - 1, and incrementing the maximum value - 1 leads
+ * to zero.
+ *
+ * After the SETUP_TIMEOUT with no button press, the system leaves the setup
+ * mode.
+ */
+static unsigned char user_params[N_USER_PARAMS] = { 0, 0, 0 };
+static unsigned char user_params_max[N_USER_PARAMS] = {
+ N_AMBIENT_ZONES+1, 2, 2
+};