The range of values from an ANGLE between directly connected to PORT B and connected to PORT A via PbHUB is different

[kotobuki]

Hi,

I'm testing my PbHUB with my M5GO and ANGLE, and I have a question.

When I connect the ANGLE to port B of the M5GO, the range of values from the ANGLE is between 0 and 4095.

However, when I connect the ANGLE to port A via the PbHUB of the M5GO, the range of values from the ANGLE is between 15 and 745 (when connected to between ch0 and ch3) or 0 and 715 (when connected to between ch4 and ch5).

I confirmed with both Arduino and UIFlow. Is this normal, or my PbHUB seems to be broken?

from m5stack import *
from m5ui import *
from uiflow import *
import time
import unit

setScreenColor(0x222222)
pbhub0 = unit.get(unit.PBHUB, unit.PORTA)

label0 = M5TextBox(10, 10, "Text", lcd.FONT_DejaVu18, 0xFFFFFF, rotate=0)

while True:
  label0.setText(str((str('ANGLE: ') + str((pbhub0.analogRead(0))))))
  wait_ms(100)
  wait_ms(2)

Best,
Shigeru

[m5stack]

of cause, they are different IC to read the raw ADC.

Pbhub use mage328

PortB use ESP32 built-in ADC

ESP32 and mega328 has different ADC resolution

[kotobuki]

@m5stack said in The range of values from an ANGLE between directly connected to PORT B and connected to PORT A via PbHUB is different:

ESP32 and mega328 has different ADC resolution

Thank you very much for your reply.

Yes, the ADC module on mega328 has a 10-bit resolution, whereas ESP32 has a 12-bit resolution. If this issue is just a resolution issue, the result should be 0 - 1023 instead of 15 - 745 or 0 - 715. If nobody can reproduce this issue, the PbHUB may be broken...