Simpletron 3 simulates a computer executing a program written in SML, Simpletron Machine Language. The user can enter a program, then watch the computer assemble and execute each statement.
Programs can manipulate integer data from -9999 to +9999 with the five operations: addition, subtraction, multiplication, integer division and exponentiation. Input data will automatically be converted to integer.
During execution certain fatal errors are detected: attempts to divide by zero, accumulator overflow, invalid operation codes. These errors will produce an error message. Other careless user errors will cause the program to crash.
The memory can be displayed at any time.