pcf8591-library 0.0.3

Library to use pcf8591 i2c analog IC with Arduino, Raspberry Pi Pico and rp2040 boards, esp32, SMT32 and ESP8266. Can read analog value and write analog value with only 2 wire.

www.mischianti.org

MicroPython Library to use i2c analog IC with arduino and esp8266. Can read analog value and write analog value with only 2 wire (perfect for ESP-01).

Changelog

• 07/11/2023: v0.0.3 Fix on read when write is active and running #Forum
• 16/05/2023: v0.0.2 Minor fix on read and write #Forum
• 18/04/2023: v0.0.1 Initial commit of stable version.

I try to simplify the use of this IC, with a minimal set of operation.

Installation

To install the library execute the following command:

pip install pcf8591-library

Constructor: Pass the address of I2C

from PCF8591 import PCF8591
from machine import I2C, Pin
    
# Initialize the I2C bus
i2c = I2C(0, scl=Pin(22), sda=Pin(21))  

# Initialize the PCF8591
pcf8591 = PCF8591(0x48, i2c)
if pcf8591.begin():
    print("PCF8591 found")

or

from PCF8591 import PCF8591

pcf8591 = PCF8591(0x48, sda=21, scl=22)
if pcf8591.begin():
    print("PCF8591 found")

To read all analog input in one

# Main loop
while True:
    # Read all analog input channels
    ain0, ain1, ain2, ain3 = pcf8591.analog_read_all()

    # Print the results
    print("AIN0:", ain0, "AIN1:", ain1, "AIN2:", ain2, "AIN3:", ain3)

    # Wait for 1 second
    utime.sleep(1)

If you want to read a single input:

print("AIN0 ", pcf8591.analog_read(PCF8591.AIN0))
print("AIN1 ", pcf8591.analog_read(PCF8591.AIN1))
print("AIN2 ", pcf8591.analog_read(PCF8591.AIN2))
print("AIN3 ", pcf8591.analog_read(PCF8591.AIN3))

If you want to write a value:

pcf8591.analog_write(255)
utime.sleep(1)
pcf8591.analog_write(128)
utime.sleep(1)
pcf8591.analog_write(0)

You can also read and write voltage

pcf8591.voltage_write(3.3)
utime.sleep(1)
pcf8591.voltage_write(1.65)
utime.sleep(1)
pcf8591.voltage_write(0)

or

print("AIN0 ", pcf8591.voltage_read(PCF8591.AIN0))
print("AIN1 ", pcf8591.voltage_read(PCF8591.AIN1))
print("AIN2 ", pcf8591.voltage_read(PCF8591.AIN2))
print("AIN3 ", pcf8591.voltage_read(PCF8591.AIN3))

For the examples I use this wire schema on breadboard: