@ Hel
I’ve just got a Badger 2040W (Great - works really well) and the recommended Galleon 400mAh 3.7V battery. I’m trying to charge it up with a Pico Lipo and Hel’s program listed here:
# This example reads the voltage from a LiPo battery connected to Pimoroni Pico LiPo
# and uses this reading to calculate how much charge is left in the battery.
# It then displays the info on the screen of Pico Display (or Pico Display 2.0).
# With Pimoroni Pico LiPo, you can read the battery percentage while it's charging.
# Save this code as main.py on your Pico if you want it to run automatically!
from machine import ADC, Pin
import time
# change to DISPLAY_PICO_DISPLAY_2 for Pico Display 2.0
from picographics import PicoGraphics, DISPLAY_PICO_DISPLAY_2
display = PicoGraphics(display=DISPLAY_PICO_DISPLAY_2, rotate=0)
display.set_backlight(0.8)
vsys = ADC(29) # reads the system input voltage
charging = Pin(24, Pin.IN) # reading GP24 tells us whether or not USB power is connected
conversion_factor = 3 * 3.3 / 65535
full_battery = 4.2 # reference voltages for a full/empty battery, in volts
empty_battery = 2.8 # the values could vary by battery size/manufacturer so you might need to adjust them
# Create some pen colours for drawing with
BLACK = display.create_pen(0, 0, 0)
GREY = display.create_pen(190, 190, 190)
GREEN = display.create_pen(0, 255, 0)
RED = display.create_pen(255, 0, 0)
while True:
# convert the raw ADC read into a voltage, and then a percentage
voltage = vsys.read_u16() * conversion_factor
percentage = 100 * ((voltage - empty_battery) / (full_battery - empty_battery))
if percentage > 100:
percentage = 100
# draw the battery outline
display.set_pen(BLACK)
display.clear()
display.set_pen(GREY)
display.rectangle(0, 0, 220, 135)
display.rectangle(220, 40, 20, 55)
display.set_pen(BLACK)
display.rectangle(3, 3, 214, 129)
# draw a green box for the battery level
display.set_pen(GREEN)
display.rectangle(5, 5, int((210 / 100) * percentage), 125)
# add text
display.set_pen(RED)
if charging.value() == 1: # if it's plugged into USB power...
display.text("Charging!", 15, 90, 240, 4)
display.text('{:.2f}'.format(voltage) + "v", 15, 10, 240, 5)
display.text('{:.0f}%'.format(percentage), 15, 50, 240, 5)
display.update()
time.sleep(0.5)
I’ve also got a 500mAh LiPo battery BAT0003
Both batteries drive the new Badger2040 W but the numbers on the displayV2 do not appear to be right.
If there is enough juice to drive the Badger I would expect to see higher values on the screen.
I’ve not used LiPos before. Am I doing things correctly?
