BASIC as programming language was chosen for its ease of use mainly from command prompt. All commands can be executed directly after Enter is pressed so it is very easy to try how connected hardware is working (LEDs, buzzer, buttons etc.)

I was searching on internet for any ideas and I have found Butterfly Basic - this basic interpreter is based on ideas from Acorn Atom basic. It was very interesting time learning how this computer worked, how assembler was incorporated in basic etc. Finally I took Butterfly basic as an idea and rewrote all code in C.

The work itself started when I got an idea how to make single-stepping in assembly on MSP430 processor. So it was for me also one of features to allow assembly programming. It differs from the idea of Acorn Atom, because I was influenced by another computer: Sharp MZ-800. So I also took ideas from here. Assembly programming is possible in "monitor" mode. It features register view/modification screen, line assembler/disassembler. It has not breakpoints but the main idea was to allow single-stepping with register view to see how instructions work and what are the results.

On home webpage, there is guide in pdf (in czech only), it contains basic explanation, many exaples and also MSP430 CPU core description with many examples both in basic and assembly. Also source code can be downloaded from that page.

For version 2, USB CDC virtual COM port was added to allow simple connection to PC for C programming. MSP430 has built-in bootloader so it is possible to programm flash memory through this CDC port.