Merge branch 'trunk' into wurkkos-ts25-boost

just getting the latest upstream changes

* trunk:
  ChangeLog for new minor release
  spacing, misc cleanup, made anchors work, fixed bad link
  there's another inherited setting now
  added more info about manual memory remembering channel mode
  space
  added info about simple vs advanced UI, and attiny85 battcheck resolution
  reworded a bit for consistency with the rest of the manual
  made new settings apply to all button LEDs on lights bigger than 8K ROM
  Manual: Add how to check which UI the user is in
  Manual: Document extra digit for battery check
  Manual: Add default for post-off voltage display
  Manual: Add channel mode to manual memory
  Manual: Update options inherited by Simple UI
  Add a feature to make RGB voltage configurable
  Improve manual - add links for navigability, and an FAQ
  Document aux LED settings in Tactical Mode

10 files changed, 280 insertions, 82 deletions

diff --git a/ChangeLog.md b/ChangeLog.md
index a60b662..63a5395 100644
--- a/ChangeLog.md
+++ b/ChangeLog.md
@@ -14,6 +14,29 @@ formats:
 
 # Next
 
+# 2025-07-07
+
+Merged a few pull requests, minor improvements, nothing big.  Users can now
+configure if and when the button LEDs light up during use and during POVD.
+
+General:
+
+- Added config options to make button LED brightness thresholds configurable.
+  Battcheck -> 7H -> Options 3+4 now set the aux low/high ramp levels, for the
+  brightness of the button while the main LEDs are on, and the brightness of
+  Post-Off Voltage Display (POVD) after turning the main LEDs off.
+  (may be options 2+3 on lights with no RGB aux, instead of 3+4)
+  (new options are only available on lights with more than 8 KiB ROM)
+- Lockout mode now only does momentary moon/low on 1st and 2nd presses.
+- Documentation updates.
+- Fixed broken GitHub CI.
+
+Hardware-specific changes:
+
+- &emisar-d3aa: Reduced moon preflash even more.
+  If it still flashes, it probably can't be fixed in software.
+
+
 # 2025-04-29
 
 Pretty minor release.  Things have been weird lately.
diff --git a/docs/anduril-manual.md b/docs/anduril-manual.md
index cdf0dd1..4e28803 100644
--- a/docs/anduril-manual.md
+++ b/docs/anduril-manual.md
@@ -30,6 +30,8 @@ more modes and features available for people who want more.
 For a full list of button mappings, scroll down to the
 [UI Reference Table](#ui-reference-table) at the end of this file.
 
+If you have a specific question, it may be covered in the [FAQ](#faq).
+
 
 Button presses
 --------------
@@ -105,15 +107,15 @@ Functions available in Simple UI include:
   - `2H`: If light is on : ramp down  
           If light is off: momentary high mode
   - `2C`: Double click to go to / from highest safe level
-  - `4C`: Lockout mode.
+  - `4C`: [Lockout mode](#lockout-mode).
 
 Some other modes and functions are available too.  When the light is
 off, these are the options:
 
-  - `3C`: Battery check mode.  (displays voltage once, then turns off)
-  - `4C`: Lockout mode.
-  - `10H`: Switch to Advanced UI.
-  - `15C` or more: Version check.
+  - `3C`: [Battery check mode](#battery-check).  (displays voltage once, then turns off)
+  - `4C`: [Lockout mode](#lockout-mode).
+  - `10H`: Switch to [Advanced UI](#advanced-ui).
+  - `15C` or more: [Version check](#version-check-mode).
 
 In Lockout mode with Simple UI, there are a few functions:
 
@@ -129,7 +131,7 @@ do one of these:
 
   In Simple UI:
 
-  - `10H`: Go to Advanced UI.
+  - `10H`: Go to [Advanced UI](#advanced-ui).
 
   In Advanced UI:
 
@@ -140,10 +142,10 @@ do one of these:
 Some lights have additional features enabled in Simple UI, at the
 manufacturer's request.  This typically includes:
 
-  - `Ramp -> 3C`: Toggle smooth or stepped ramp shape.
-  - `Ramp -> 5H`: Sunset timer.
-  - `Off -> 7C/7H`: Change the aux LED pattern.
-  - `Lockout -> 7C/7H`: Change the aux LED pattern.
+  - `Ramp -> 3C`: Toggle smooth or stepped [ramp shape](#ramping--stepped-ramping-modes).
+  - `Ramp -> 5H`: [Sunset timer](#sunset-timer).
+  - `Off -> 7C/7H`: Change the [aux LED pattern](#aux-leds--button-leds).
+  - `Lockout -> 7C/7H`: Change the [aux LED pattern](#aux-leds--button-leds).
 
 Old versions (before 2024-08) also allowed access to strobe/mood modes, which
 can be dangerous, so if you have one of those, *think twice about letting kids
@@ -156,7 +158,7 @@ Simple UI can be configured in several ways, but not while Simple UI is
 active.  So go to the Advanced UI, configure things, then go back to
 Simple UI.
 
-In Advanced UI's "Off" mode:
+In [Advanced UI](#advanced-ui)'s "Off" mode:
 
   - `10H`: Configure Simple UI.
 
@@ -173,12 +175,17 @@ and they will carry over to Simple UI:
   - ramp style (smooth / stepped)
   - smooth ramp speed
   - ramp-after-moon style
+  - smooth steps
   - memory settings
   - auto-lock settings
   - aux LED settings
   - voltage calibration
+  - post-off voltage display
+  - aux led low and high ramp levels
   - thermal regulation settings
   - hardware-specific "misc menu" settings
+  - channel modes
+  - channel mode for number blinks
 
 
 Advanced UI
@@ -187,6 +194,13 @@ Advanced UI
 Most of the information below this is for the Advanced UI.  Anything not
 already noted above is blocked in the Simple UI.
 
+To check which UI the user is in, Simple UI or Advanced UI, enter battery check
+mode with `3C` from Off.  In Simple UI, the battery voltage is displayed only
+once, but in Advanced UI, the battery voltage is checked and displayed
+repeatedly.
+
+To return to Simple UI from advanced UI, enter 10C while the light is off.
+
 
 Ramping / Stepped Ramping Modes
 -------------------------------
@@ -205,15 +219,15 @@ Advanced UI's ramp.
 There are four ways to access ramping mode when the light is off:
 
   - `1C`: Turn on at the memorized brightness.
-    (see below for details about what "memorized" means)
+          (see below for details about what "memorized" means)
 
   - `1H`: Turn on at the floor level.  Let go after the light turns on to
-    stay at the floor level, or keep holding to ramp up.
+          stay at the floor level, or keep holding to ramp up.
 
   - `2C`: Turn on at the ceiling level.
 
-  - `2H`: Turn on at full power, turn off when released.  (momentary turbo)
-        (in Simple UI, this uses the ceiling level instead of turbo)
+  - `2H`: Turn on at full power, turn off when released.  (momentary turbo)  
+          (in Simple UI, this uses the ceiling level instead of turbo)
 
 While the light is on, a few actions are available:
 
@@ -222,25 +236,28 @@ While the light is on, a few actions are available:
           (or if it has regulated down, "bump" back up to turbo)  
           (turbo level / behavior is configurable)
   - `1H`: Change brightness (up).  
-          If the button was released less than a second ago, or if it's already
-          at the ceiling, it goes down instead.
+          If the button was released less than a second ago,  
+          or if it's already at the ceiling, it goes down instead.
   - `2H`: Change brightness (down).
 
-  - `3C`: Switch to the other ramp style.  (smooth / stepped)  
-          (or activate the next channel mode, when more than one is enabled)  
+  - `3C`: Switch to the other [ramp style](#ramping--stepped-ramping-modes).
+          (smooth / stepped)  
+          (or activate the next [channel mode](#channel-modes),
+          when more than one is enabled)  
           (then use 6C instead, for smooth / stepped toggle)
   - `6C`: Switch to the other ramp style.  (when `3C` is mapped to next channel)
 
   - `3H`: Momentary turbo (when current channel has no tint to ramp).
-  - `3H`: Tint ramping (only when current channel has adjustable tint).
+  - `3H`: [Tint ramping](#channel-modes)
+          (only when current channel has adjustable tint).
   - `4H`: Momentary turbo, when `3H` is mapped to tint.
 
-  - `4C`: Go to lockout mode.
+  - `4C`: Go to [lockout mode](#lockout-mode).
 
-  - `5C`: Go to momentary mode.
-  - `5H`: Start a sunset timer.  Details are below in the Sunset Timer section.
+  - `5C`: Go to [momentary mode](#momentary-mode).
+  - `5H`: Start a [sunset timer](#sunset-timer).
 
-  - `7H`: Ramp config menu.
+  - `7H`: [Ramp config menu](#ramp-config-menu).
     - Item 1: Floor level.
     - Item 2: Ceiling level.
     - Item 3:  
@@ -252,6 +269,7 @@ While the light is on, a few actions are available:
         4 = Quarter speed, ~10s.
 
   - `10C`: Activate manual memory and save the current brightness.
+           Also saves current channel mode, on multi-channel lights.
   - `10H`: Ramp extras config menu.
     - Item 1: Disable manual memory and go back to automatic memory.  
               (doesn't matter what value the user enters at the prompt)
@@ -333,16 +351,16 @@ Other Modes
 Anduril has several other modes too.  To access these, press the button
 more than 2 times when the light is off:
 
-  - `3C`: Blinky / utility modes, starting with battery check.
-  - `3H`: Strobe modes, starting with the most recently used strobe.
-  - `4C`: Lockout mode.
-  - `5C`: Momentary mode.
-  - `6C`: Tactical mode.
-  - `7C` / `7H`: Aux LED configuration.
-  - `9H`: Misc Config menu. (only on some lights)
-  - `10H`: Simple UI configuration menu.
-  - `13H`: Factory reset (on some lights).
-  - `15C` or more: Version check.
+  - `3C`: [Blinky / utility modes](#blinky--utility-modes), starting with battery check.
+  - `3H`: [Strobe modes](#strobe--mood-modes), starting with the most recently used strobe.
+  - `4C`: [Lockout mode](#lockout-mode).
+  - `5C`: [Momentary mode](#momentary-mode).
+  - `6C`: [Tactical mode](#tactical-mode).
+  - `7C` / `7H`: [Aux LED configuration](#aux-leds--button-leds).
+  - `9H`: [Misc Config menu](#misc-config-menu). (only on some lights)
+  - `10H`: [Simple UI](#simple-ui) configuration menu.
+  - `13H`: [Factory reset](#factory-reset) (on some lights).
+  - `15C` or more: [Version check](#version-check-mode).
 
 
 Lockout Mode
@@ -376,6 +394,7 @@ lockout mode has two levels:
 
   - `3H`: Next channel mode (if more than one is enabled).
 
+<a id="autolock-config"></a>
 It is also possible to make the light lock itself automatically after
 being turned off.  To enable this, go to lockout mode and use a `10H`
 action to activate the auto-lock config menu.  Release the button after
@@ -386,10 +405,9 @@ timeout to N minutes.
            A value of zero disables the auto-lock feature.
            So, to turn off auto-lock, don't click at all.
 
-And on lights which have aux LEDs, there may be additional functions:
+On lights which have aux LEDs, there may be additional functions:
 
-  - `7C` / `7H`: Change Lockout Mode's aux LED pattern.  More details on
-    this below, in a separate section.
+  - `7C` / `7H`: Change Lockout Mode's [aux LED pattern](#aux-leds--button-leds).
 
 
 Blinky / Utility Modes
@@ -399,10 +417,10 @@ Click 3 times from Off to access Anduril's blinky / utility modes.  This
 always starts at battery check and the user can proceed to other blinky
 modes if Advanced UI is enabled.  The sequence is:
 
-  - Battery check.
-  - Temperature check (if light has a temperature sensor).
-  - Beacon mode.
-  - SOS mode (if enabled).
+  - [Battery check](#battery-check).
+  - [Temperature check](#temperature-check) (if light has a temperature sensor).
+  - [Beacon mode](#beacon-mode).
+  - [SOS mode](#sos-mode) (if enabled).
 
 In all of these modes, some basic actions are available:
 
@@ -417,14 +435,30 @@ In more detail, this is what each blinky / utility mode does:
 
 ### Battery check:
 
-Blinks out the battery voltage per cell.  Full is 4.2V, empty is
-about 3.0V.  The light blinks the whole-number digit first, pauses,
-then blinks out the "tenths" digit.  Then a longer pause, and it
-repeats.
-So for 4.2V, it would be "blink-blink-blink-blink .. blink-blink".
+Blinks out the battery voltage per cell.  Full is 4.20V, empty is
+about 3.00V.  The light blinks the whole-number digit first, pauses,
+then blinks out the "tenths" digit, pauses, then blinks out the "hundredths"
+digit, in 0.02V steps.  So for 4.16V, it would be "4 blinks, 1 blink,
+6 blinks".  Then if it is in Advanced UI, it pauses for a bit longer and
+repeats.  In Simple UI, it turns off after one readout.
 
 A "zero" digit is represented by a very quick blink.
 
+The battery check format has changed a few times:
+
+  - For Anduril 2 from 2024-04 or later, the battery voltage resolution is
+    0.02V steps (the last digit can be 0, 2, 4, 6, or 8).
+
+  - For Anduril 2 from 2023-12 or later, the battery voltage resolution is
+    0.025V steps (the last digit can be 0, 2, 5, or 7).
+
+  - For Anduril 2 from 2023-12 or earlier, the battery voltage resolution is
+    0.1V, so the light blinks the whole-number digit first, pauses, then blinks
+    out the "tenths" digit.  Then a longer pause, and it repeats.
+
+  - On old attiny85 lights with only 8 KiB of ROM, battery voltage resolution
+    is 0.1V, even on newer versions of Anduril.
+
 On lights with more than one set of LEDs, pressing `3C` during batt
 check mode can select which set of LEDs (which channel mode) it uses
 to blink out numbers.
@@ -449,11 +483,23 @@ The voltage config menu has these settings:
      `12C`: +0.25V  
      `13C`: +0.30V
 
-  2. Post-off voltage display timeout.  (only on lights with RGB aux)  
+  2. Post-off voltage display timeout.  (only on lights with RGB aux)
      This setting determines how many seconds the RGB aux LEDs
      display the voltage color after the torch goes to sleep.  Click
      once per desired second, or zero times to turn this function
-     off.
+     off.  The default is 4 seconds.
+
+  3. Aux low ramp level.  Controls behavior of aux button LEDs while the main
+     LEDs are on.  Below this ramp level, button LEDs will not be lit up while
+     the main LEDs are on.  At or above this level, button LEDs light up at the
+     "low" brightness level.  Setting it to 0 keeps the button LEDs off
+     completely while the main LEDs are on.  
+     Also controls brightness of post-off voltage display.
+
+  4. Aux high ramp level.  At or above this ramp level, button LEDs light up at
+     the "high" brightness level.  Setting it to 0 disables button's high aux
+     mode while the main LEDs are on.  
+     Also controls brightness of post-off voltage display.
 
 ### Temperature check:
 
@@ -522,12 +568,12 @@ In all of these modes, a few actions are available:
   - `1H`: Increase brightness, or strobe faster.  (except lightning)
   - `2H`: Decrease brightness, or strobe slower.  (except lightning)
   - `4C`: Previous strobe / mood mode.
-  - `5C`: Go to momentary mode, for a momentary strobe.
+  - `5C`: Go to [momentary mode](#momentary-mode), for a momentary strobe.
           (this is useful for light painting)
 
 Additionally, candle mode has one more action:
 
-  - `5H`: Activate Sunset Timer, and/or add 5 minutes to the timer.
+  - `5H`: Activate [Sunset Timer](#sunset-timer), and/or add 5 minutes to the timer.
 
 In more detail, here is what each mode does:
 
@@ -635,6 +681,8 @@ This assumes the light has a ramp 150 levels long.  Strobe modes start
 at the ramp size plus 1, so it may be different if a light has a
 different ramp size.
 
+In Tactical Mode, the aux LED settings are inherited from Lockout Mode.
+
 
 Configuration Menus
 -------------------
@@ -780,7 +828,7 @@ several formats:
 If the version doesn't include a model number, you may be able to find
 the model in the PRODUCTS file to see which firmware model it probably uses:
 
-  https://bazaar.launchpad.net/~toykeeper/flashlight-firmware/anduril2/view/head:/PRODUCTS
+  https://toykeeper.net/torches/PRODUCTS
 
 
 Protection Features
@@ -890,6 +938,7 @@ lights.  The number of settings in the Misc Config Menu depends on the
 hardware model and the firmware version.
 
 
+<a id="channel-modes"></a>
 Channel Modes (a.k.a. Tint Ramping or Multi Channel controls)
 -------------------------------------------------------------
 
@@ -938,9 +987,9 @@ smooth or stepped brightness ramp.  Additionally, when a channel mode
 has nothing to adjust with `3H`, the `3H` action also reverts to its
 single-channel behavior -- momentary turbo.
 
-The Misc Config Menu (`Off -> 9H`) may also have a setting to choose a
-tint ramp style.  There are a few styles available, by entering
-different numbers into that config menu:
+The [Misc Config Menu](#misc-config-menu) (`Off -> 9H`) may also have
+a setting to choose a tint ramp style.  There are a few styles
+available, by entering different numbers into that config menu:
 
   0: smooth ramp  
   1: middle tint only  
@@ -951,6 +1000,20 @@ This setting only applies to modes with channel ramping (i.e. tint
 ramping), and only when that mode uses the default `3H` event handler.
 Custom channel modes may work differently.
 
+On lights with channel modes, manual memory (`Ramp -> 10C`) saves the
+current brightness *and* channel mode.
+
+
+FAQ
+---
+
+* Q: Why do the aux LEDs come on whenever I switch the light off, regardless
+  of aux settings?
+* A: This is the post-off voltage display feature. It can be configured or
+  disabled under [battery check](#battery-check) mode.
+
+* Q: What can I do to contribute to Anduril development?
+* A: See [Contributing](https://github.com/ToyKeeper/anduril#contributing).
 
 
 UI Reference Table
@@ -1007,6 +1070,7 @@ This is a table of all button mappings in Anduril, in one place:
 |                |        |         | 2: ceiling
 |                |        |         | 3: speed / steps
 | Ramp           | Full   | `10C`   | Turn on manual memory and save current brightness
+|                |        |         | (and current channel mode)
 | Ramp           | Full   | `10H`   | Ramp Extras config menu:
 |                |        |         | 1: switch to automatic mem, not manual mem
 |                |        |         | 2: set manual mem timeout
@@ -1065,14 +1129,18 @@ This is a table of all button mappings in Anduril, in one place:
 | Batt check     | Full   | `3C`    | Next channel mode (for number blinks only)
 | Batt check     | Full   | `7H`    | Voltage config menu
 |                |        |         | 1: voltage correction factor
-|                |        |         |    ...
-|                |        |         |    5: -0.10V
-|                |        |         |    6: -0.05V
-|                |        |         |    7: no correction
-|                |        |         |    8: +0.05V
-|                |        |         |    9: +0.10V
-|                |        |         |    ...
+|                |        |         | ... 5: -0.10V
+|                |        |         | ... 6: -0.05V
+|                |        |         | ... 7: no correction
+|                |        |         | ... 8: +0.05V
+|                |        |         | ... 9: +0.10V
 |                |        |         | 2: post-off voltage display seconds
+|                |        |         | 3: aux low ramp level
+|                |        |         | ... 0: disabled
+|                |        |         | ... 1+: light up at this ramp level
+|                |        |         | 4: aux high ramp level
+|                |        |         | ... 0: disabled
+|                |        |         | ... 1+: brighter at this ramp level
 
 | Mode           | UI     | Button  | Action
 | :---           | :--    | ------: | :-----
diff --git a/fsm/ramping.c b/fsm/ramping.c
index 743e619..f8ca4ec 100644
--- a/fsm/ramping.c
+++ b/fsm/ramping.c
@@ -8,14 +8,20 @@
 
 #ifdef HAS_AUX_LEDS
 inline void set_level_aux_leds(uint8_t level) {
+    #ifdef USE_AUX_THRESHOLD_CONFIG
+        #define AUX_BRIGHTNESS ((level > cfg.button_led_low_ramp_level) \
+            << (level > cfg.button_led_high_ramp_level))
+    #else
+        #define AUX_BRIGHTNESS ((level > 0) + (level > DEFAULT_LEVEL))
+    #endif
     #ifdef USE_INDICATOR_LED_WHILE_RAMPING
         // use side-facing aux LEDs while main LEDs are on
         if (! go_to_standby) {
         #ifdef USE_INDICATOR_LED
-            indicator_led((level > 0) + (level > DEFAULT_LEVEL));
+            indicator_led(AUX_BRIGHTNESS);
         #endif
         #ifdef USE_BUTTON_LED
-            button_led_set((level > 0) + (level > DEFAULT_LEVEL));
+            button_led_set(AUX_BRIGHTNESS);
         #endif
         }
     #else  // turn off front-facing aux LEDs while main LEDs are on
@@ -27,12 +33,15 @@ inline void set_level_aux_leds(uint8_t level) {
             #ifdef USE_AUX_RGB_LEDS
                 rgb_led_set(0);
                 #ifdef USE_BUTTON_LED
-                    button_led_set((level > 0) + (level > DEFAULT_LEVEL));
+                    button_led_set(AUX_BRIGHTNESS);
                 #endif
             #endif
         }
         #endif
     #endif
+    #ifdef AUX_BRIGHTNESS
+    #undef AUX_BRIGHTNESS
+    #endif
 }
 #endif  // ifdef HAS_AUX_LEDS
 
@@ -41,15 +50,28 @@ inline void set_level_aux_leds(uint8_t level) {
 #include "anduril/aux-leds.h"  // for rgb_led_voltage_readout()
 inline void set_level_aux_rgb_leds(uint8_t level) {
     if (! go_to_standby) {
+        #ifdef USE_AUX_THRESHOLD_CONFIG
+        if (level > cfg.button_led_low_ramp_level) {
+            rgb_led_voltage_readout(level > cfg.button_led_high_ramp_level);
+        }
+        #else
         if (level > 0) {
             rgb_led_voltage_readout(level > USE_AUX_RGB_LEDS_WHILE_ON);
-        } else {
+        }
+        #endif
+        else {
             rgb_led_set(0);
         }
         // some drivers can be wired with RGB or single color to button
         // ... so support both even though only one is connected
         #ifdef USE_BUTTON_LED
+            #ifdef USE_AUX_THRESHOLD_CONFIG
+            button_led_set(
+                    (level > cfg.button_led_low_ramp_level)
+                    << (level > cfg.button_led_high_ramp_level));
+            #else
             button_led_set((level > 0) + (level > DEFAULT_LEVEL));
+            #endif
         #endif
     }
 }
diff --git a/ui/anduril/anduril.c b/ui/anduril/anduril.c
index 383acbc..a17ecf2 100644
--- a/ui/anduril/anduril.c
+++ b/ui/anduril/anduril.c
@@ -286,9 +286,17 @@ void loop() {
     StatePtr state = current_state;
 
     #ifdef USE_AUX_RGB_LEDS_WHILE_ON
-    // display battery charge on RGB button during use
-    if (state == steady_state)
-        rgb_led_voltage_readout(actual_level > USE_AUX_RGB_LEDS_WHILE_ON);
+        // display battery charge on RGB button during use
+        if (state == steady_state) {
+            #ifdef USE_AUX_THRESHOLD_CONFIG
+            // only show voltage if feature is enabled and
+            // we are above the configured minimum ramp level
+            if (actual_level > cfg.button_led_low_ramp_level)
+                rgb_led_voltage_readout(actual_level > cfg.button_led_high_ramp_level);
+            #else
+                rgb_led_voltage_readout(actual_level > USE_AUX_RGB_LEDS_WHILE_ON);
+            #endif
+        }
     #endif
 
     if (0) {}  // placeholder
diff --git a/ui/anduril/aux-leds.c b/ui/anduril/aux-leds.c
index 7356666..50ce5c5 100644
--- a/ui/anduril/aux-leds.c
+++ b/ui/anduril/aux-leds.c
@@ -125,7 +125,18 @@ void rgb_led_update(uint8_t mode, uint16_t arg) {
           && (ticks_since_on > 0)  // don't blink red on 1st frame
         ) {
         // use high mode if regular aux level is high or prev level was high
-        pattern = 1 + ((2 == pattern) | (prev_level >= POST_OFF_VOLTAGE_BRIGHTNESS));
+        #ifdef USE_AUX_THRESHOLD_CONFIG
+            // always high if configured for high aux
+            // otherwise 0/1/2 depending on recent main LED brightness
+            // (using >= makes it off by 1, but allows POVD at boot time)
+            if (pattern != 2)
+                pattern = (prev_level >= cfg.button_led_low_ramp_level)
+                    << (prev_level > cfg.button_led_high_ramp_level);
+        #else
+            pattern = 1
+                + ((2 == pattern)
+                   | (prev_level >= POST_OFF_VOLTAGE_BRIGHTNESS));
+        #endif
         // voltage mode
         color = RGB_LED_NUM_COLORS - 1;
     }
diff --git a/ui/anduril/battcheck-mode.c b/ui/anduril/battcheck-mode.c
index c7c80dd..460c58a 100644
--- a/ui/anduril/battcheck-mode.c
+++ b/ui/anduril/battcheck-mode.c
@@ -51,7 +51,7 @@ uint8_t battcheck_state(Event event, uint16_t arg) {
     return EVENT_NOT_HANDLED;
 }
 
-#ifdef USE_VOLTAGE_CORRECTION
+#if defined(USE_VOLTAGE_CORRECTION) || defined(USE_POST_OFF_VOLTAGE) || defined(USE_AUX_THRESHOLD_CONFIG)
 // the user can adjust the battery measurements... on a scale of 1 to 13
 // 1 = subtract 0.30V
 // 2 = subtract 0.25V
@@ -61,21 +61,35 @@ uint8_t battcheck_state(Event event, uint16_t arg) {
 // ...
 // 13 = add 0.30V
 void voltage_config_save(uint8_t step, uint8_t value) {
-    #ifdef USE_POST_OFF_VOLTAGE
-        if (2 == step) cfg.post_off_voltage = value;
-        else
-    #endif
-    if (value) cfg.voltage_correction = value;
+    switch (step) {
+        #if defined(USE_AUX_THRESHOLD_CONFIG)
+        case button_led_low_ramp_level_step:
+            // 0 clicks = 255 = never turn on
+            cfg.button_led_low_ramp_level = value - 1;
+            break;
+        case button_led_high_ramp_level_step:
+            // 0 clicks = 255 = never turn on
+            cfg.button_led_high_ramp_level = value - 1;
+            break;
+        #endif
+
+        #ifdef USE_POST_OFF_VOLTAGE
+        case post_off_voltage_config_step:
+            cfg.post_off_voltage = value;
+            break;
+        #endif
+
+        #ifdef USE_VOLTAGE_CORRECTION
+        default:
+            if (value) cfg.voltage_correction = value;
+            break;
+        #endif
+    }
 }
 
 uint8_t voltage_config_state(Event event, uint16_t arg) {
-    #ifdef USE_POST_OFF_VOLTAGE
-        #define VOLTAGE_CONFIG_STEPS  2
-    #else
-        #define VOLTAGE_CONFIG_STEPS  1
-    #endif
     return config_state_base(event, arg,
-                             VOLTAGE_CONFIG_STEPS,
+                             voltage_config_num_steps - 1,
                              voltage_config_save);
 }
 #endif  // #ifdef USE_VOLTAGE_CORRECTION
diff --git a/ui/anduril/battcheck-mode.h b/ui/anduril/battcheck-mode.h
index b505b68..2ff7c81 100644
--- a/ui/anduril/battcheck-mode.h
+++ b/ui/anduril/battcheck-mode.h
@@ -5,8 +5,23 @@
 
 uint8_t battcheck_state(Event event, uint16_t arg);
 
-#ifdef USE_VOLTAGE_CORRECTION
+#if defined(USE_VOLTAGE_CORRECTION) || defined(USE_POST_OFF_VOLTAGE) || defined(USE_AUX_THRESHOLD_CONFIG)
 void voltage_config_save(uint8_t step, uint8_t value);
 uint8_t voltage_config_state(Event event, uint16_t arg);
 #endif
 
+typedef enum {
+    voltage_cfg_zero = 0,
+    #ifdef USE_VOLTAGE_CORRECTION
+        voltage_correction_config_step,
+    #endif
+    #ifdef USE_POST_OFF_VOLTAGE
+        post_off_voltage_config_step,
+    #endif
+    #if defined(USE_AUX_THRESHOLD_CONFIG)
+        button_led_low_ramp_level_step,
+        button_led_high_ramp_level_step,
+    #endif
+    voltage_config_num_steps
+} voltage_config_steps_e;
+
diff --git a/ui/anduril/config-default.h b/ui/anduril/config-default.h
index 1b34e8c..51249f6 100644
--- a/ui/anduril/config-default.h
+++ b/ui/anduril/config-default.h
@@ -199,6 +199,14 @@
 #define USE_LOWPASS_WHILE_ASLEEP
 #endif
 
+// if the light has aux LEDs and enough ROM, let the user choose whether
+// the aux LEDs should be on while the main LEDs are on
+#if (ROM_SIZE > 10000)
+// can be enabled even if no aux LEDs exist,
+// will simply do nothing in that case
+#define USE_AUX_THRESHOLD_CONFIG
+#endif
+
 // if there's tint ramping, allow user to set it smooth or stepped
 #define USE_STEPPED_TINT_RAMPING
 #define DEFAULT_TINT_RAMP_STYLE 0  // smooth
diff --git a/ui/anduril/load-save-config-fsm.h b/ui/anduril/load-save-config-fsm.h
index d189d3a..a69d1b1 100644
--- a/ui/anduril/load-save-config-fsm.h
+++ b/ui/anduril/load-save-config-fsm.h
@@ -97,6 +97,10 @@ typedef struct Config {
         uint8_t therm_ceil;
         int8_t therm_cal_offset;
     #endif
+    #ifdef USE_AUX_THRESHOLD_CONFIG
+        uint8_t button_led_low_ramp_level;
+        uint8_t button_led_high_ramp_level;
+    #endif
 
     ///// aux LEDs
     #ifdef USE_INDICATOR_LED
diff --git a/ui/anduril/load-save-config.h b/ui/anduril/load-save-config.h
index 3ad477c..f5afb29 100644
--- a/ui/anduril/load-save-config.h
+++ b/ui/anduril/load-save-config.h
@@ -169,5 +169,30 @@ Config cfg = {
         .jump_start_level = DEFAULT_JUMP_START_LEVEL,
     #endif
 
+    #if defined(USE_AUX_THRESHOLD_CONFIG)
+        // config for RGB voltage. We need to check these here rather than
+        // setting defaults in `config-default.h` as we only know *after*
+        // defaults are loaded if `USE_AUX_RGB_LEDS_WHILE_ON` is set or unset
+        // (in `CFG_H`).
+        #ifdef USE_AUX_LEDS_WHILE_ON_INITIAL_MINIMUM_LEVEL
+            .button_led_low_ramp_level = USE_AUX_LEDS_WHILE_ON_INITIAL_MINIMUM_LEVEL,
+        #else
+            .button_led_low_ramp_level = 0,  // default
+        #endif
+        #if (USE_AUX_RGB_LEDS_WHILE_ON + 0)
+            // if USE_AUX_RGB_LEDS_WHILE_ON is an int, passes. If blank (undefined
+            // or defined with no value), evaluates to `(+0)` which evaluates to
+            // false.
+            .button_led_high_ramp_level = USE_AUX_RGB_LEDS_WHILE_ON,
+        #else
+            #ifdef USE_AUX_RGB_LEDS
+                //#warning "USE_AUX_RGB_LEDS_WHILE_ON defined but has no value. Setting to default value."
+                .button_led_high_ramp_level = 25 - 1,  // default
+            #else
+                .button_led_high_ramp_level = DEFAULT_LEVEL - 1,  // default
+            #endif
+        #endif
+    #endif
+
 };