SFT-1071: Port FE battery ADC code to Gen 2 repo

FE battery icon was not updating as battery drained

ports/stm32/boards/Passport/manifest.py

@@ -237,6 +237,7 @@
        ('tasks/__init__.py',
         'tasks/apply_passphrase_task.py',
         'tasks/auto_shutdown_task.py',
+        'tasks/battery_adc_task.py',
         'tasks/bip85_seed_task.py',
         'tasks/calculate_file_sha256_task.py',
         'tasks/card_task.py',

ports/stm32/boards/Passport/modules/main.py

@@ -150,6 +150,8 @@ def go():
 
     if passport.HAS_FUEL_GAUGE:
         common.loop.create_task(tasks.fuelgauge_task())
+    else:
+        common.loop.create_task(tasks.battery_adc_task())
 
     # Setup the main task
     common.loop.create_task(tasks.main_task())

ports/stm32/boards/Passport/modules/screens/main_screen.py

@@ -93,7 +93,7 @@ def update_background(self):
                 idx = NUM_ACCOUNT_TEXTURES
 
             overlay_name = 'IMAGE_SCREEN_OVERLAY_{}'.format(idx)
-            print('overlay_name={}'.format(overlay_name))
+            # print('overlay_name={}'.format(overlay_name))
             with LocalStyle(self.overlay) as default:
                 default.bg_img(getattr(lv, overlay_name))
                 default.radius(8)
@@ -110,7 +110,7 @@ def update_background(self):
                 idx = NUM_ACCOUNT_TEXTURES
 
             overlay_name = 'IMAGE_SCREEN_OVERLAY_{}'.format(idx)
-            print('overlay_name={}'.format(overlay_name))
+            # print('overlay_name={}'.format(overlay_name))
             with LocalStyle(self.overlay) as default:
                 default.bg_img(getattr(lv, overlay_name))
                 default.radius(8)

ports/stm32/boards/Passport/modules/styles/colors.py

@@ -63,6 +63,7 @@
     DIGIT_BORDER_COLOR_FOCUSED_HEX = FD_BLUE_HEX
     PIN_ENTRY_MESSAGE_COLOR_HEX = FD_BLUE_HEX
     BATTERY_FILL_COLOR_HEX = FD_BLUE_HEX
+    BATTERY_FILL_BG_COLOR_HEX = TEXT_GREY
     SCROLLBAR_BG_COLOR_HEX = BLACK_HEX
 else:
     # On monochrome, white is white, and everything else is black
@@ -122,6 +123,7 @@
     DIGIT_BORDER_COLOR_UNFOCUSED_HEX = BLACK_HEX
     PIN_ENTRY_MESSAGE_COLOR_HEX = BLACK_HEX
     BATTERY_FILL_COLOR_HEX = BLACK_HEX
+    BATTERY_FILL_BG_COLOR_HEX = WHITE_HEX
     SCROLLBAR_BG_COLOR_HEX = BLACK_HEX
 
 WHITE = lv.color_hex(WHITE_HEX)
@@ -178,6 +180,7 @@
 DIGIT_BORDER_COLOR_UNFOCUSED = lv.color_hex(DIGIT_BORDER_COLOR_UNFOCUSED_HEX)
 PIN_ENTRY_MESSAGE_COLOR = lv.color_hex(PIN_ENTRY_MESSAGE_COLOR_HEX)
 BATTERY_FILL_COLOR = lv.color_hex(BATTERY_FILL_COLOR_HEX)
+BATTERY_FILL_BG_COLOR = lv.color_hex(BATTERY_FILL_BG_COLOR_HEX)
 SCROLLBAR_BG_COLOR = lv.color_hex(SCROLLBAR_BG_COLOR_HEX)
 
 # Account Colors

ports/stm32/boards/Passport/modules/tasks/__init__.py

@@ -6,6 +6,8 @@
 
 if passport.HAS_FUEL_GAUGE:
     from .fuelgauge_task import fuelgauge_task
+else:
+    from .battery_adc_task import battery_adc_task
 
 from .apply_passphrase_task import apply_passphrase_task
 from .auto_shutdown_task import auto_shutdown_task

ports/stm32/boards/Passport/modules/tasks/battery_adc_task.py

@@ -0,0 +1,89 @@
+# SPDX-FileCopyrightText: 2022 Foundation Devices, Inc. <hello@foundationdevices.com>
+# SPDX-License-Identifier: GPL-3.0-or-later
+#
+# battery_adc_task.py - Task for updating the battery level in the UI by reading the battery ADC
+#                       (Founder's Edition only).
+
+
+from micropython import const
+from uasyncio import sleep_ms
+import common
+
+NUM_SAMPLES = const(2)
+
+battery_segments = [
+    {'v': 3100, 'p': 100},
+    {'v': 3100, 'p': 100},
+    {'v': 3025, 'p': 75},
+    {'v': 2975, 'p': 50},
+    {'v': 2800, 'p': 25},
+    {'v': 2400, 'p': 0},
+]
+
+
+def calc_battery_percent(current, voltage):
+    # print('calc_battery_percent(): voltage={}'.format(voltage))
+    if voltage > 3100:
+        voltage = 3100
+    elif voltage < 2400:
+        voltage = 2400
+
+    # First find the segment we fit in
+    for i in range(1, len(battery_segments)):
+        curr = battery_segments[i]
+        prev = battery_segments[i - 1]
+        if voltage >= curr['v']:
+            # print('curr[{}]={}'.format(i, curr))
+
+            rise = curr['v'] - prev['v']
+            # print('rise={}'.format(rise))
+
+            run = curr['p'] - prev['p']
+            # print('run={}'.format(run))
+
+            if run == 0:
+                # print('zero run, so return value directly: {}'.format(curr['p']))
+                return curr['p']
+
+            # Slope
+            m = rise / run
+            # print('m={}'.format(m))
+
+            # y = mx + b  =>  x = (y - b) / m  =>  b = y - mx
+
+            # Calculate y intercept for this segment
+            b = curr['v'] - (m * curr['p'])
+            # print('b={}'.format(b))
+
+            percent = int((voltage - b) / m)
+            # print('Returning percent={}'.format(percent))
+            return percent
+
+    return 0
+
+
+async def battery_adc_task():
+    while True:
+        # Read the current values -- repeat this a number of times and average for better results
+        total_current = 0
+        total_voltage = 0
+        for i in range(NUM_SAMPLES):
+            (current, voltage) = common.powermon.read()
+            voltage = round(voltage * (44.7 + 22.1) / 44.7)
+            total_current += current
+            total_voltage += voltage
+            await sleep_ms(1)  # Wait a bit before next sample
+        current = total_current / NUM_SAMPLES
+        voltage = total_voltage / NUM_SAMPLES
+
+        # Update the actual battery level in the UI
+        level = calc_battery_percent(current, voltage)
+        # print('New battery level = {}'.format(level))
+
+        common.ui.set_battery_level(level)
+
+        # If battery is too low, try to avoid the doom loop of reboots by shutting down automatically
+        if level <= 2:
+            common.system.shutdown()
+
+        await sleep_ms(60000)

ports/stm32/boards/Passport/modules/views/battery_indicator.py

@@ -7,7 +7,7 @@
 import lvgl as lv
 from micropython import const
 from views import View, Icon
-from styles.colors import BATTERY_FILL_COLOR, WHITE, TEXT_GREY
+from styles.colors import BATTERY_FILL_COLOR, BATTERY_FILL_BG_COLOR, WHITE
 from styles import Stylize, LocalStyle
 
 _LEFT_MARGIN = const(2)
@@ -32,7 +32,7 @@ def __init__(self, outline_color=WHITE):
         self.bg_fill.set_size(_FILL_MAX_WIDTH, _FILL_HEIGHT)
         self.bg_fill.set_pos(_LEFT_MARGIN, _TOP_MARGIN)
         with Stylize(self.bg_fill) as default:
-            default.bg_color(TEXT_GREY)
+            default.bg_color(BATTERY_FILL_BG_COLOR)
 
         self.fill = View()
         self.fill.set_height(_FILL_HEIGHT)

simulator/sim_modules/passport/__init__.py

@@ -33,10 +33,16 @@ def random_bytes(self, buf, _source):
 
 class Powermon:
     def __init__(self):
-        pass
+        self.level = 2350
+        self.increment = -25
 
     def read(self):
-        return (0, 3500)
+        result = (0, self.level)
+        self.level += self.increment
+        if self.level <= 1750 or self.level >= 2350:
+            self.increment = -self.increment
+        # print('Powermon simulator: {}'.format(result))
+        return result
 
 
 class System: