I've been getting the vsys voltage using this, with CircuitPython:
I use it to measure the voltage of the li-ion battery that's running my Pico W. Now I've hooked a sensor up to ADC2, and the vsys readings are inflated.
Before it would read the li-ion voltage, typically 3.6 to 4.2 volts. Now I get readings like 8.63 or 8.67. If I remove the sensor from ADC2, the vsys reading goes back to normal.
Is there any way to get an accurate vsys reading while using ADC2?
Code:
from board import VOLTAGE_MONITORdef get_vsys(): try: global vsys_voltage pin = analogio.AnalogIn(VOLTAGE_MONITOR) adc_reading = pin.value adc_voltage = (adc_reading * pin.reference_voltage) / 65535 vsys_voltage = adc_voltage * 3 pin.deinit() except Exception as e: print("get_vsys problem: ", e)Before it would read the li-ion voltage, typically 3.6 to 4.2 volts. Now I get readings like 8.63 or 8.67. If I remove the sensor from ADC2, the vsys reading goes back to normal.
Is there any way to get an accurate vsys reading while using ADC2?
Statistics: Posted by david3 — Thu Sep 17, 2026 11:55 am — Replies 4 — Views 44
![[QLD, NSW, VIC] Samsung 65](http://files.ozbargain.com.au/n/31/978831l.jpg?h=8d64f0c6)
/pic7955059.jpg)
