MicroPython Thermal Printer

This is the MicroPython port of Python Thermal Printer by Adafruit, available elsewhere on GitHub.

Read the full story at https://kapusta.cc/2017/12/11/thermal-printer-library-for-micropython/.

The summary of changes

1. Removed Python 2.x code
2. Removed writeToStdout()
3. Replaced Serial with machine.UART
4. Removed support for pre-2.68 firmware
5. Removed image printing method, because it depended on Python Imaging Library
6. Disabled calls to wake() and reset() at initialization
7. Fixes to sleepAfter() and wake()

Additions

• printBitmapFromFile() - allows for printing the bitmap from file on disk, instead of reading it from array of bytes like printBitmap() does.
• printBMPImage() - allows for printing the actual .bmp image. Supports 1-bit Windows BMP format only, up to 384px wide.
• heat dots, heat time and heat interval settings are parametrized in the initializer to fine tune printer output.

Usage

See printertest.py for usage example.

Testing

So far I tested it only with LoPy version 1. Works fine, besides printing large bitmaps that required too much memory for the LoPy (for the bitmap provided with printertest.py) - hence printBitmapFromFile().