Here’s a complete set of instructions on how to setup a simple development system that is completely open source. It uses the libopencm3 open source library.
This is a demo program to print to the POS58 (aka ZJ-5890K) USB thermal receipt printer using Python under Linux (tested on a Raspberry Pi). This is printer is sold under different companies, but is made by Zjiang.
This has been tested on LinuxMint 18, a Raspberry Pi 3 B+ running Raspbian Stretch Lite, and a Raspberry Pi Zero W (pictured below).
The ESP8266 WiFi modules have been a blast to play with. Lots of folks are making inexpensive IoT devices with these, such as sending real-time temperature and humidity as MQTT data for crowdsourced data or home automatoin, but why not add a clock so you can also use it daily?
In this project, I have add a simple 4-digit 7-segment LED display to an ESP8266 running as an MQTT client to make a clock sending temperature and humidity readings.
A hummingbird decided to nest in our potted olive tree so, of course, I had to scour the web to see if I could make a wildlife camera using my favorite single-board computer, the $10 Raspberry Pi Zero W. The result was fantastic!
A friend was poking around with these QS30-1 nixie modules from nixieclock.org. He mentioned that all the projects on the ‘net used an Arduino but he really wanted to use a Raspberry Pi.
I looked at the Arduino code and Nixie board schematics and wrote a Python driver for it.