Getting Started: Coding Assembly

How to Program a Robot

Robot Programmer Tutorial

Introduction

Writing code is extremely easy. There are a few commands for you to understand that you can use to control a robot. This manual will provide help on how to actually program a robot and is intended for beginners. Additional examples are available on the Internet.

As we progress through this guide we will build a list of key words and concepts used.

Each Robot consists of hardware and software. The software controls what the hardware does. To act as a "middleman" between the software and the hardware is the Operating System. Your cellphone most likely uses an IOS or Android Operating System; your computer most likely use Windows or Linux as an Operating System.

Here, we use an operating system named "BothOS".

BothOs

BothOS, or BOS, like any operating system contain what is known as "Registers" to store data, manipulate data and transfer data. Your job as a programmer is to write the code to set the registers at the right times to the "right" values. Since it is up to YOU to decide what a good strategy is for a robot it is therefor also up to YOU to decide what these "right values" are depending on your strategy. For example, to tell a gun to shoot in a direction you would need to tell this to BOS; then after this you may want to turn your robot around, which you also need to tell BOS; then maybe you want to speed up as fast as you can. Every action you want your robot to take during a match you need to tell BOS through code.

How does Assembly code look?

There are a few simple rules when it comes to telling BOS what to do:

Rule 1: One line represents one command.

For BOS to understand you you must sepereate each command by writing then below each other. For example sake, let say our command that we want to execute is "TEST" then we can ask BOS to execute it say 3 times by writing it 3 times in separate rows as

TEST

TEST

TEST

BOS will NOT accept multiple commands per line.

Rule 2: Commands can contain parameters.

A parameter is along with a command. A parameter tells BOS on what DATA you want it to execute the command on. For example, in the above ADD command example, which adds 2 numbers together, the command therefore accepts 2 parameters for it to make sense.

Thus, to add numbers together with the ADD command it would be used as such:

ADD 5 3 ;This would ADD 5 and 3 together, resulting in 8 (but the 8 is not stored anywhere)

ADD ax 5 ;This would ADD the AX register with 3, resulting in AX being 3 more than whatever it was before this command

ADD ax bx ;This would ADD the AX register with the BX register.

Some commands require no parameters, some require 1 parameter and some require 2 parameters. No commands require more than 2 parameters.

Rule 3: Commands can affect registers.

Once a command has executed, BOS needs to store the result in a register. If you had a value stored in the specific register used by a command then the value will be overwritten.

For example, the ADD ax 5 command would add 5 to the value of ax then STORE it in the ax register, while the ADD bx 5 would add 5 to the value of bx and store it in bx (and so on).

There are 19 assembly commands in total.

There are commands to help with mathematics, there are commands that help with communicating with devices and there are commands to do logical steps.

Your entire program can consist of a single command but your robot would not be very smart. Therefor you are free to use any set of commands to accomplish your strategy. BOS will accept your command, execute it and move to the next command. Once all the code in the Main program has executed past the last line of code then it will start again from the top. This loop will continue until the match is over or your bot has been destroyed.

Before understanding the code, lets take a look at the available "registers".

Registers

Registers are memory locations that your code will modify in order to tell BothOs what to do. Your program will use registers to store information. These registers can also be used for your own strategy purposes.

The registers available for you to use are named as follow:

Ax

Bx

Cx

Dx

Ex

Fx

Gx

There are also 3 registers that BothOs use and you should not use.

IP

CMPL

CMPR

Assembly Commands

There are 19 commands for you to use.

NOP

Parameters: 0

Description: Waste Time

Example Code:

NOP

NOP

NOP ;Wasted 3 clock cycles

MOV param1 param2

Parameters: 2

Description: Moves register or value parem2 into register parem1

Example Code:

MOV ax 3 ; moves the value of 3 into ax

MOV bx 5 ; moves the value of 5 into bx

MOV bx ax; moves the value of AX (which is 3 in this example) into bx and overwrite bx

INT param1

Parameters: 2

Description: Sends all the registers to an interrupt device. An "interrupt" device is a built-in device that you can access regardless of what components your robot are made out of. Things such as the match time, number of enemies etc. can be obtained via interrupt calls. There is an extra section dedicated to the INT command.

Example Code:

INT 1 ; This would cause interrupt device number 1 to execute.

INT 5 ; This would cause interrupt device number 5 to execute.

IO param1

Parameters: 2

Description: Sends all the registers to a device to use. The IO command is at the heart of every program you will use it to interact with the devices attached to your robot such as guns, legs, sensors and any other external device. There is an extra section dedicated to the IO command.

Example Code:

IO 0 ; This would interact with the device or weapon mapped at port 5,

IO 0 ; This would interact with the device or weapon mapped at port 1

ADD param1 param2

Parameters: 2

Description: Adds parem2 to parem1 and store it in parem1

Example Code:

ADD ax 5 ; adds 5 to the value of ax and store it in ax

SUB param1 param2

Parameters: 2

Description: Subracts parem2 from parem1 and store it in parem1

Example Code:

MOV ax 10 ; moves 10 into ax register

SUB ax 5 ; subtracts 5 from the value of ax (which is 10 from the line above) and store it in ax (thus ax is 5)

SUB ax 2 ; subtracts 5 from the value of ax (which is 5 from the line above) and store it in ax (thus ax is now 3)

MPY param1 param2

Parameters: 2

Description: Multiply parem2 by parem1 and store it in parem1

Example Code:

MOV ax 25 ; moves 25 into ax register

MOV bx 2 ; moves 2 into bx register

MPY ax 2 ; multiply the value of ax (which is 25 from the line above) with 2 and store it in ax (thus ax is 50)

MPY ax bx ; multiply the value of ax (which is 50 from the line above) with bx (which is 2) and store it in ax (thus ax is 100)

DIV param1 param2

Parameters: 2

Description: Divides parem1 by parem2 and store it in parem1

Example Code:

MOV ax 100 ; moves 100 into ax register

MOV bx 5 ; moves 5 into bx register

DIV ax 2 ; divides the value of ax (which is 100 from the line above) with 2 and store it in ax (thus ax is 50)

DIV ax bx ; divides the value of ax (which is 50 from the line above) with bx (which is 5) and store it in ax (thus ax is 10)

MOD param1 param2

Parameters: 2

Description: Mods parem1 by parem2 and store it in parem1

Example Code:

MOV ax 9; moves 9 into ax register

MOD ax 4 ; mods the value of ax (which is 9 from the line above) with 4 and store it in ax (thus ax is 1)

CALL param1

Parameters:1

Description: Calls/Executes a function stored outside of your code.

Example Code:

Call SecondFunction; will execute the code stored in the function named "SecondFunction"

CMP param1 param2

Parameters: 2

Description: Compared param1 with param2 and stores the result

Example Code:

CMP ax, 5; compare the value stored in the ax register with a value of "5"

CMO bx ax ; compare the value stored in the bx register with the value stored in the ax register.

JMP param1

Parameters: 1

Description: Jumps code execution to start at the label defined by param1

Example Code:

MOV AX 1 ; moves the value of 1 into the ax register

LBL ExampleJump ; define a label named "ExampleJump"

MOV AX 2 ; moves the value of 1 into the ax register

JMP ExampleJump ; jumps code execution to the label address of "ExampleJump"

MOV AX 4 ; this line of code will not execute because the jump does not allow code execution to ever actually reach here.

JLS param1 param2

Parameters: 2

Description: Jumps to a defined label IF param1 is LESS than param2

Example Code:

MOV ax 2

MOD bx 3

CMP ax bx ; compares ax to bx

JLS "ShootEnemy" ; if ax is LESS than bx then code execution will continue at the label defined as "ShootEnemy"

JGR param1 param2

Parameters: 2

Description: Jumps to a defined label IF param1 is GREATER than param2

Example Code:

MOV ax 2

MOD bx 1

CMP ax bx ; compares ax to bx

JGR "ShootEnemy" ; if ax is GREATER than bx then code execution will continue at the label defined as "ShootEnemy"

JNE param1 param2

Parameters: 2

Description: Jumps to a defined label IF param1 is NOT EQUAL TO param2

Example Code:

MOV ax 2

MOD bx 3

CMP ax bx ; compares ax to bx

JNE "ShootEnemy" ; if ax is NOT EQUAL TO bx then code execution will continue at the label defined as "ShootEnemy"

JEQ param1 param2

Parameters: 2

Description: Jumps to a defined label IF param1 is EQUAL TO param2

Example Code:

MOV ax 2

MOD bx 3

CMP ax bx ; compares ax to bx

JEQ "ShootEnemy" ; if ax is EQUAL to bx then code execution will continue at the label defined as "ShootEnemy"

JGE param1 param2

Parameters: 2

Description: Jumps to a defined label IF param1 is GREATER AND EQUAL TO param2

Example Code:

MOV ax 2;

MOD bx 3 ;

CMP ax bx ; compares ax to bx

JLS "ShootEnemy" ; if ax is GREATER AND EQUAL to bx then code execution will continue at the label defined as "ShootEnemy"

JLE param1 param2

Parameters: 2

Description: Jumps to a defined label IF param1 is LESS THAN AND EQUAL To param2

Example Code:

MOV ax 2; moves 9 into ax register

MOD bx 3 ; mods the value of ax (which is 9 from the line above) with 4 and store it in ax (thus ax is 1)

CMP ax bx ; compares ax to bx

JLS "ShootEnemy" ; if ax is LESS THAN AND EQUAL TO bx then code execution will continue at the label defined as "ShootEnemy"

Interrupts

INT 0 - Self Destruct

Input: NONE

Output: NONE

Description: Destroy self and take as many enemies with me as possible.

INT 1 - Reset

Input: NONE

Output: NONE

Description: Reset program to start over.

INT 2 - Locate

Input: NONE

Output: NONE

Description: Gets the robot's own location.

INT 3 - Overburn

Input: NONE

Output: NONE

Description: Sets the overburn & overclocking rate.

INT 4 - ID

Input: NONE

Output: NONE

Description: Gets the robot's pown ID for the match.

INT 5 - Timer

Input: NONE

Output: NONE

Description: Get the current match time.