From cb013b6e3bf4cf33d6b3fa0a78e8f68c7f1bdf8a Mon Sep 17 00:00:00 2001
From: Yukai Li <yukaili.geek@gmail.com>
Date: Wed, 21 Jun 2023 19:16:41 -0600
Subject: [PATCH] Reimplement get_battery_level() and launcher battery display

---
 badger_os/launcher.py                         | 30 +++++++++++++++++
 .../PIMORONI_BADGER2040W/lib/badger_os.py     | 33 +++++++------------
 2 files changed, 41 insertions(+), 22 deletions(-)

diff --git a/badger_os/launcher.py b/badger_os/launcher.py
index b54f102..c970ce7 100644
--- a/badger_os/launcher.py
+++ b/badger_os/launcher.py
@@ -21,6 +21,9 @@
     # Otherwise restore previously running app
     badger_os.state_launch()
 
+# for e.g. 2xAAA batteries, try max 3.4 min 3.0
+MAX_BATTERY_VOLTAGE = 4.0
+MIN_BATTERY_VOLTAGE = 3.2
 
 display = badger2040.Badger2040()
 display.set_font("bitmap8")
@@ -49,6 +52,29 @@ def map_value(input, in_min, in_max, out_min, out_max):
     return (((input - in_min) * (out_max - out_min)) / (in_max - in_min)) + out_min
 
 
+def draw_battery(level, x, y):
+    # Outline
+    display.set_pen(15)
+    display.rectangle(x, y, 19, 10)
+    # Terminal
+    display.rectangle(x + 19, y + 3, 2, 4)
+    display.set_pen(0)
+    display.rectangle(x + 1, y + 1, 17, 8)
+    if level < 1:
+        display.set_pen(0)
+        display.line(x + 3, y, x + 3 + 10, y + 10)
+        display.line(x + 3 + 1, y, x + 3 + 11, y + 10)
+        display.set_pen(15)
+        display.line(x + 2 + 2, y - 1, x + 4 + 12, y + 11)
+        display.line(x + 2 + 3, y - 1, x + 4 + 13, y + 11)
+        return
+    # Battery Bars
+    display.set_pen(15)
+    for i in range(4):
+        if level / 4 > (1.0 * i) / 4:
+            display.rectangle(i * 4 + x + 2, y + 2, 3, 6)
+
+
 def draw_disk_usage(x):
     _, f_used, _ = badger_os.get_disk_usage()
 
@@ -110,6 +136,10 @@ def render():
     display.set_pen(0)
     display.rectangle(0, 0, WIDTH, 16)
     draw_disk_usage(90)
+    if badger2040.is_wireless():
+        vbat = badger_os.get_battery_level()
+        bat = int(map_value(vbat, MIN_BATTERY_VOLTAGE, MAX_BATTERY_VOLTAGE, 0, 4))
+        draw_battery(bat, WIDTH - 22 - 3, 3)
     display.set_pen(15)
     display.text("badgerOS", 4, 4, WIDTH, 1.0)
 
diff --git a/firmware/PIMORONI_BADGER2040W/lib/badger_os.py b/firmware/PIMORONI_BADGER2040W/lib/badger_os.py
index ce4cc19..d11ed35 100644
--- a/firmware/PIMORONI_BADGER2040W/lib/badger_os.py
+++ b/firmware/PIMORONI_BADGER2040W/lib/badger_os.py
@@ -7,28 +7,17 @@
 
 
 def get_battery_level():
-    return 0
-    # Battery measurement
-    vbat_adc = machine.ADC(badger2040.PIN_BATTERY)
-    vref_adc = machine.ADC(badger2040.PIN_1V2_REF)
-    vref_en = machine.Pin(badger2040.PIN_VREF_POWER)
-    vref_en.init(machine.Pin.OUT)
-    vref_en.value(0)
-
-    # Enable the onboard voltage reference
-    vref_en.value(1)
-
-    # Calculate the logic supply voltage, as will be lower that the usual 3.3V when running off low batteries
-    vdd = 1.24 * (65535 / vref_adc.read_u16())
-    vbat = (
-        (vbat_adc.read_u16() / 65535) * 3 * vdd
-    )  # 3 in this is a gain, not rounding of 3.3V
-
-    # Disable the onboard voltage reference
-    vref_en.value(0)
-
-    # Convert the voltage to a level to display onscreen
-    return vbat
+    from machine import Pin, ADC
+
+    # Setup pins
+    Pin(25, Pin.OUT, value=1)  # Deselect Wi-Fi module
+    Pin(29, Pin.IN, pull=None)  # Set VSYS ADC pin floating
+
+    # VSYS measurement
+    vsys_adc = ADC(29)
+    vsys = (vsys_adc.read_u16() / 65535) * 3 * 3.3
+
+    return vsys
 
 
 def get_disk_usage():