# HG changeset patch
# User Mychaela Falconia <falcon@freecalypso.org>
# Date 1632453835 0
# Node ID 231bceb7d95cf1bf3d990337c2cb7c9da479521b
# Parent  a75eefbf8be4d9dd9628b50f0be8295dd149a788
skip switch-on buzzer beep in UI-enabled builds

diff -r a75eefbf8be4 -r 231bceb7d95c src/cs/system/main/create_RVtasks.c
--- a/src/cs/system/main/create_RVtasks.c	Fri Sep 24 02:03:08 2021 +0000
+++ b/src/cs/system/main/create_RVtasks.c	Fri Sep 24 03:23:55 2021 +0000
@@ -581,7 +581,26 @@
     Switch_ON();
 #endif
 
-#if (_GSM==1)
+/*
+ * FreeCalypso change: we omit the BZ_BeyKeep_ON() action
+ * in UI-enabled builds, which will also have FCBM.
+ * In these builds the switch-on feedback to the user is the phone
+ * or devboard LCD lighting up, hence the buzzer feedback becomes
+ * redundant.
+ *
+ * Besides UI-level redundancy, another problem with ringing the
+ * buzzer here occurs in charging boot scenarios, when Iota switch-on
+ * marks the transition from precharge to fw-driven charging.
+ * Experience shows that when the battery just barely made it past
+ * Iota switch-on threshold, the extra current draw caused by either
+ * the buzzer or the LCD backlight may be enough to cause an emergency
+ * switch-off, and several such cycles will occur before the battery
+ * is precharged enough to make it past this next threshold.
+ * Eliminating the buzzer ringing action and leaving just the LCD
+ * with its backlight seems like the right course of action in this
+ * scenario.
+ */
+#if (_GSM==1) && !defined(RVM_FCBM_SWE)
     BZ_KeyBeep_ON ();          // Audio feedback if ON/OFF pushed
 #endif // if (_GSM==1)