Program in Hexadecimal with the Tiny Machine-Code Monitor

Today, if you learn to program a computer, you might pick up Python, a version of C, or any number of other high-level languages that power much of our world. When computing first began to enter private homes, however, the only way to program them was with a hexadecimal keypad with only a 7-segment display as a monitor. While this advancement is surely a good thing, according to David Johnson-Davies’ Technoblogy project write-up, only knowing high level languages means that you miss out on some of the fun and understanding that comes from programming in machine code.

To facilitate learning and experimentation with this type of programming, the Tiny Machine-Code Monitor project provides all you need to program in machine code, including a simple monitor that shows off four lines of text, a hex keypad, and basic navigation keys. An ATtiny85 microcontroller is tasked with running the device, and interprets the MINIL (MINiature Interpreted Language) code entered by the user. MINIL, developed by Johnson-Davies, uses only 16 operation codes, or opcodes. Even with this basic (not BASIC) instruction set, you can write a number of interesting programs with it, as seen on this example page.

If you’d like to go back to an even more rudimentary computer interface, you’ll want to also check out the Digirule2. It takes inputs not from a hexadecimal keypad, but from a series of binary buttons, and even lets you measure items while you’re at it!