cjn-PiTools 1.2.1

cjn's library of Raspberry Pi functions, drivers, tools, ...

cjn_PiTools - A collection of modules for Raspberry Pi projects

cjn_PiTools is comprised of several modules (follow links to respective documentation)

NOTE: These links point to the github repo since relative links to other .md files do not work on PyPI.

Module	Description/Purpose
PiBlinky	A multiple threaded LED driver for Raspberry Pi
PiOLED	Display multi-line messages on a shared Raspberry Pi connected OLED display
DS18B20	DS18B20 temperature sensor library using the w1_therm kernel driver
initW1buses	Initialize the W1 buses and set write permission on found therm_bulk_read file(s)
ADC121C	ADC121C* 12-bit ADC library for Raspberry Pi
SHT3x	SHT3x Temperature/RH sensor library for Raspberry Pi
HTU21D	HTU21D Temperature/RH sensor library for Raspberry Pi
MCP23008	MCP23008 8-Bit I/O Expander library for Raspberry Pi
PCA9548	PCA9548A/TCA9548A I2C port expander library for Raspberry Pi
shared	Classes and functions used across cjn_PiTools

These drivers work with both RPi.GPIO / smbus2 (for local control) and pigpio for (local and remote control).

Developed and tested on Raspbian GNU/Linux 11 (bullseye) and Python 3.9.2, and supported on all higher versions.

In this documentation, "tool script" refers to a Python project that imports and uses cjn_PiTools. Some may be simple scripts, and others may themselves be installed packages.

Installation and usage

If using the RPi.GPIO and/or smbus2 drivers:

pip install cjn_PiTools

If using the pigpio driver:

pip install cjn_PiTools[pigpio]

• And you will also need to install the pigpiod daemon (sudo apt install pigpiod) and start it manually or at boot. Here's a systemd service file for starting pigpiod at boot:

    [Unit]
    Description=Daemon required to control GPIO pins via pigpio
  
    [Service]
    ExecStart=/usr/local/bin/pigpiod -l
    Type=forking
    TimeoutStopSec=20
  
    [Install]
    WantedBy=multi-user.target
  

Key changes since the prior major public release (1.1)

V1.2.1 Changes

• HTU21D dummy user reg reads for measurement reads stability, init changed do_soft_reset > do_reset, consistent with SHT3x.
• PCA9548 monitor_ch feature
• ADC121C read_conversion_result force_address switch added to address issue when a second process accesses the device and leaves the address register set elsewhere

V1.2 Changes PiOLED uses shared memory, changed from display_file - cjnfuncs 3.2 dependency PiOLED add toolname to pioled_display_driver pioled_shm_lock and pioled_go_flag .get_lock() calls PiOLED taillog command Debug logging of MCP23008 set_register() and set_bits() values

Revision history

• 1.2.1 260526 HTU21D dummy user reg reads for measurement reads stability PCA9548 monitor_ch ADC121C read_conversion_result force_address switch added PiOLED tweaks HTU21D init changed do_soft_reset > do_reset, consistent with SHT3x
• 1.2 260506 PiOLED uses shared memory, changed from display_file - cjnfuncs 3.2 dependency PiOLED add toolname to pioled_display_driver pioled_shm_lock and pioled_go_flag .get_lock() calls PiOLED taillog command Debug logging of MCP23008 set_register() and set_bits() values
• 1.1.1 260401 - pyproject.toml cleanup, keywords
• 1.1 260401 - Added ADC121C, HTU21D, MCP23008, PCA9548, and SHT3x drivers
• 1.0 260207 - New. Bundled PiBlinky, PiOLED, initW1buses, and DS18B20 modules