HT16K33 Drivers 4.0.1

This repo provides Python drivers for the Holtek HT16K33 controller chip and various display devices based upon it, such as the Adafruit 0.8-inch 8x16 LED Matrix FeatherWing and the SparkFun Qwiic Alphanumeric Display.

The drivers support both CircuitPython and MicroPython applications. They communicate using I²C.

The library also supports generic seven-segment displays wired up to an HT16K33, which can drive up to eight these LEDs. The HT16K33 may be on a board of your own design, or on a third-party one, such as the Adafruit 16x8 LED Matrix Driver Backpack . LED units you can connect range from single digits up to combinations of multi-digit units.

Connect your HT16K33 column pins to each LED's digit selection pin, and its row pins to the LED's segment selection pins.

Display Drivers

Driver (Click for docs)	Example Product
Small 4-digit, 7-segment LED	Adafruit 0.56-inch 4-digit, 7-segment LED display
Large 4-digit, 7-segment LED	Adafruit 1.2-inch 4-digit, 7-segment LED display
Small 4-digit, 14-segment LED	SparkFun Qwiic Alphanumeric Display, Adafruit 0.54in Alphanumeric Display
8x8 monochrome matrix LED	Adafruit Mini 0.8-inch 8x8 LED Matrix
8x8 bi-colour matrix LED	Adafruit 1.2-inch 8x8 bi-color LED matrix backpack
16x8 FeatherWing matrix LED	Adafruit 0.8-inch 8x16 LED Matrix FeatherWing
Standalone HT16K33	Adafruit 16x8 LED Matrix Driver Backpack

Further drivers may be added in due course.

Import the Drivers

The driver package comprises a parent generic HT16K33 class and child classes for various displays themselves. All your code needs to do is import the latter. For example:

from ht16k33 import HT16K33Segment

You can then instantiate the driver object. This requires a configured I2C bus object.

You will need at least one display driver file, eg. ht16k33segmentgen.py and ht16k33.py in your project folder.

Install the Drivers

MicroPython Manual Install

Use the pyboard or mpremote command line tools to copy the ht16k33 directory to your board's lib directory.

MicroPython MIP Install

You can install the drivers using MicroPython's MIP system. This requires a board running MicroPython 1.20 or above and connected to the Internet. Add the following to your code:

import mip
mip.install('github:smittytone/HT16K33-Python')

If your board is not Internet-capable, you can install locally using the mpremote tool:

mpremote mip install github:smittytone/HT16K33-Python

Install Script

Alternatively, use our convenient installer script:

./tools/mpinstall.sh

To install pre-compiled versions of the library files, run:

./tools/mpinstall.sh mpy

This requires MicroPython's mpy-cross tool installed on your computer.

CircuitPython Manual Install

Copy ht16k33 directory to the mounted board's lib folder.

Reducing Memory Usage

Adding the driver code may prove too much for certain CircuitPython devices which have limited amounts of memory. To overcome this, use MicroPython’s mpy-cross compiler. This will compile the raw Python into a highly compact form as a .mpy file. Copy ht16k33.mpy and the device-specific .mpy file to your device in place of the .py versions.

For MicroPython boards, I recommend you use the mpinstall.sh script to compile and install .mpy versions if the library files all in one go.

Documentation

You can find documentation for all of the drivers at smittytone.net.

Python Package Index

This code is now available via the Python Package Index for folks using Thonny and other code-pulling IDEs.

Release Notes

• 4.0.1 16 August 2024
  • Minor fixes/improvements.
  • Add experimental rotate() method to ht16k33Segmentbig.py.
• 4.0.0 8 May 2024
  • Completely reorganise the library files into their own directory.
  • Add device installation script for MicroPython users - thanks, @ubidefeo.
  • Add HT16K33SegmentGen CircuitPython examples.
  • Use Raspberry Pi Pico for all examples.
• 3.5.3 15 January 2024
  • Remove the .mpy versions and provide instructions instead.
  • Fix incorrect selection of blink rate 0.5Hz — thanks, @Karrp.
• 3.5.2 11 December 2023
  • Add mip support — thanks, @ubidefeo (no code changes).
• 3.5.1 30 October 2023
  • Add provisional PyPI support (no code changes).
• 3.5.0 2 September 2023
  • Add HT16K33SegmentGen a generic, 1-8 digit 7-segment driver — thanks, @vader7071.
• 3.4.2 14 February 2023
  • Fix an error when a space is shown as a zero — thanks, @asasine.
• 3.4.1 14 November 2022
  • Correct VK16K33 naming.
  • Fix VK16K33 colon setting and unsetting — thanks, Dietmar Schüller.
• 3.4.0 6 October 2022
  • Allow the colon and decimal point on SparkFun Qwiic Alphanumeric Display).
• 3.3.1 13 September 2022
  • 14-segment character-set numerals now match 7-segment equivalents.
  • Assorted code tweaks.
  • Wrangle and extend examples.
  • Remove old docs.
  • Big thanks to @akbiocca for assistance with this release.
• 3.3.0 5 August 2022
  • Add rotate() method to HT16K33Segment.
• 3.2.0 26 July 2022
  • Support the Adafruit 0.54in Alphanumeric Display via ht16k33segment14.py.
  • Bug fixes.
• 3.1.0 16 February 2022
  • Add ht16k33segment14.py to support the SparkFun Qwiic Alphanumeric Display.
• 3.0.2 23 November 2020
  • Refactor out some ht16k33matrix.py code.
• 3.0.1 7 November 2020
  • Correct variable name in ht16k33matrix.py.
• 3.0.0 6 November 2020
  • Initial public release.

Licence and Copyright

This repository’s source code and documentation is copyright © 2024, Tony Smith (@smittytone).

The HTK16K33 driver and subsidiary display drivers are licensed under the MIT License.