Pi pico - multiplexer - oled and Bq34z100

[Manjo80]

Hallo, I‘m trying to make a skript on a pi pico to show the chaging stat of multiple batteries with an Bq34z100 in it, using an oled for every battery being charged. I‘m using an Muitiplexer Hailege TCA9548 TCA9548A I2C IIC Multiplexer Breakout Board 8 Channel Expansion Board Module Development Board. On every channel I will install an oled and a plugg for the battery. For the moment I‘m testing the Mux with 2 Oled an one battery.

This is may main skript.

from machine import I2C, Pin
import time
from oled import SSD1306_I2C
from read_temperature import read_temperature
from read_soc import read_soc
from read_soh import read_soh
from read_ttf import read_ttf
from read_charge_cycles import read_charge_cycles

# I2C-Adressen der Geräte
OLED_ADDRESS = 0x3C
BQ34Z100_ADDRESS = 0x69
MUX_ADDRESS = 0x70

# Initialisiere den I2C-Bus
i2c = I2C(1, sda=Pin(2), scl=Pin(3), freq=400000)

# Schleife für jeden Kanal
channel = 1
while channel < 9:
    i2c.writeto(MUX_ADDRESS, b'\x00')
    i2c.writeto(MUX_ADDRESS, bytes([channel]))
    
    # Initialisiere das OLED-Display, falls vorhanden
    if OLED_ADDRESS in i2c.scan():
        scanned_addresses = i2c.scan()
        print(f"Scanned I2C addresses on Channel {channel}: {scanned_addresses}")
        oled = SSD1306_I2C(128, 64, i2c)
    
    if OLED_ADDRESS in i2c.scan() and BQ34Z100_ADDRESS in i2c.scan():
        # Lesen und anzeigen der Temperatur, wenn der BQ34Z100 verfügbar ist
        temperature = read_temperature(i2c, BQ34Z100_ADDRESS)
        if temperature is not None:
            print(f"Temperature on Channel {channel}: {temperature} °C")
            
        # Lesen und anzeigen der read_soc, wenn der BQ34Z100 verfügbar ist
        soc = read_soc(i2c, BQ34Z100_ADDRESS)
        if soc is not None:
            print(f"soc on Channel {channel}: {soc}")
            
        # Lesen und anzeigen der read_soh, wenn der BQ34Z100 verfügbar ist
        soh = read_soh(i2c, BQ34Z100_ADDRESS)
        if soh is not None:
            print(f"soh on Channel {channel}: {soh}")
            
        # Lesen und anzeigen der read_ttf, wenn der BQ34Z100 verfügbar ist
        ttf = read_ttf(i2c, BQ34Z100_ADDRESS)
        if ttf is not None:
            print(f"ttf on Channel {channel}: {ttf}")
            
        # Lesen und anzeigen der read_charge_cycles, wenn der BQ34Z100 verfügbar ist
        charge_cycles = read_charge_cycles(i2c, BQ34Z100_ADDRESS)
        if charge_cycles is not None:
            print(f"charge_cycles on Channel {channel}: {charge_cycles}")

    else:
        # Display löschen, um es auszuschalten, wenn kein bq34z100 auf diesem Kanal vorhanden ist
        if OLED_ADDRESS in i2c.scan():
            oled.fill(0)
            oled.show()
            
    # Gehe zum nächsten Kanal
    print(f"Channel aktiv {channel}")
    channel += 1
    print(f"switch to Channel {channel}")
    # Wenn alle Kanäle durchlaufen wurden, warte 40 Sekunden
    if channel == 9:
        channel = 1
        time.sleep(40)

For the moment I have the Problem on every channel I can see devices using the i2c.scan() even on channels with no devices. Maybee there are some lines in the skript making no sense, because I‘m testing and searching for my error. And for the moment I have not yet added to display the data on the oleds. This makes no sense until I have found a solution for my i2c.scan() problem

Greeds

Joel

[Manjo80]

Ok I have found this error I can‘t count the channels like this line channel_mask = 1 << (channel - 1) now the adresses are correct. Now i have done the first readout from the bq34z100, what seams working but the informations are totaly wrong. Has someone here already worked with an Bq34z100?

[peterhinch]

Have you got pullup resistors on the I2C lines?

[Manjo80]

Yes