MacroCalculator

Custom Mechanical USB Keypad + Standalone Calculator written in MicroPython

Hardware:

• Custom 24 Key Matrix PCB
  • Supports hot-swapable MX-style key switches
  • Hand solderable (Difficulty: medium-high due to small surface mount diodes)
  • Standard PC Numpad Keys
  • 7 extra macro keys
  • Sockets for MCU and LCD via pin headers.
• RPi Pico 2 (RP2350 MCU)
• 72x284 resolution ST7789 LCD Screen: 16px font = 4 lines x 17 characters

Software / Firmware

Custom Python App running on lvgl/lv_micropython firmware.

The NumLock key toggles between two modes:

• Calc mode:
  • Basic calculator functionality
  • 17 digits of decimal precision
  • Basic expression evaluation
  • Named variables assignable to the macro keys
  • Scrollable history buffer
• Keypad mode:
  • Basic USB HID Numpad
  • Macro keys programmable with MicroPython for nearly unlimited flexibility.