If you are doing lots of prototyping probably you found yourself writing a separate programs for just testing particular things. These could be getting ADC value, setting port values, read pins. Antoker found himself doing this too often and so he started a command line interface project for MCUs.
A specific code is loaded to MCU and it starts accepting short commands via serial interface. This is somehow similar to Unix based environment, just a lot simpler. By running simple commands you can track time, check Flash and RAM space, play around with ADC, GPIO, USART and probably other peripherals. More complex commands can be scripted and run in blocks like loops. Using other features like pool, jumps it makes a programing language. Currently command line interface is adapted for TI Steallaris and Tiva microcontroller series.