Robot Interpreter is a simulation environment for the ROBOT computer described in Chapter 5 of The Computer Continuum by Kurt Lauckner and Mildred Lintner, 2nd Edition, (c) 2001 Prentice Hall, Inc.  It was originally implemented by  Dr. Martin C. Carlisle and Lt Col Keith Shomper of the United States Air Force Academy  Department of Computer Science. 

The environment window is shown below:

Programming the Robot

A ROBOT program is a sequence of instructions (see Table 5.3.1 for the instruction set).  At any time, the user can change the program by clicking on the appropriate Value in the Value column and entering a different 8 digit binary number.  This program can be saved and reloaded using the Load and Save Program choices from the Robot menu.  If desired, you can set the PC by clicking on the value in the bottom right corner of the screen.  Furthermore, you can shift the instructions down, or delete an instruction and shift the remaining instructions up by selecting the appropriate choice from the Robot menu.  Note that inserting or deleting an instruction will cause the operands of all GOTO instructions after the current PC to be incremented or decremented accordingly.

Changing the Environment

The room size may be selected using the "Change Room Size" choice from the Scene menu.  The program will randomly place the specified number of doors.  By clicking on the border of the room, a square can be changed from wall to door and back.  Particular room arrangements may be saved and loaded using the Load and Save Scene commands from the Scene menu.

Positioning the robot

At any time, the user can position the robot by clicking anywhere inside the room.  Also, buttons are provided for selecting the robot's direction, and for toggling the state of the robot's light and arms.  These buttons may be used at any time.  Note that you cannot place the robot in an impossible position (arms up next to a wall).  Attempting to raise the arms when next to the wall turns on the warning light.

Running the program

"Reset robot" resets the PC to 0 (the value of the program counter is displayed in the lower right corner, and as a red arrow next to the instruction about to be executed), lowers the robot's arms, and turns off its light.  "Do Next" will fetch and execute the next ROBOT instruction, but does nothing if the robot has executed a stop instruction or has gone through a door.  "Run until Stop" repeatedly fetches and executes instructions.  The speed of simulation may be adjusted using the slider.  The simulation stops when the user pushes stop, or the robot does a STOP instruction, or the robot exits the room through a door.  To start again, push "Reset robot".