Thanks to Jeff Parsons who created an emulator environment that runs, among other platforms, a virtual Superboard II computer (also known as the Challenger 1P) you too can enjoy the wonderous experience of programming a 6502 home computer based upon a teletype input system.
This is exactly how I learned to write both BASIC and 6502 machine code from magazines such as 'Computing Today' and 'Byte'.
The BASIC interpreter in the machine ROM was written by a little-known company called Microsoft.
Unfortunately, this implementation does not function properly on a mobile device due to the way the key presses are registered.
But, if you are using a laptop or computer click this button to start the emulator Fire It Up
I would suggest reading all of the text on the emulator page to learn how to get the system to operate if you have not used an actual Superboard or C1P before.