This is a plugin to help developing stuff in Calcutron-33 Assembly used by the made-up Calcutron-33 microprocessor, designed for teaching beginners to assembly programming. To get a quick introduction here is a simple program which reads a number N from input and writes to output every from N until 1.
// count down program
loop:
INP x1 // load number to count down from
decrement:
OUT x1 // write out counter to tape
DEC x1 // count down by one
BGT x1, x0, decrement
JMP loop
HLT
You use INP and OUT to handle I/O and HLT is used to stop execution of a program.